스파이 체킹

A BLU의 파이로가 Harvest에서 부활 지점을 떠나는 팀원들에게 성공적인 스파이 체킹을 했습니다.

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클릭하시면 들을 수 있습니다

— 스카웃이 스파이에게 대항하며

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스파이 체킹 은 아군의 팀원들이 적군 스파이를 찾아내고 사살하기 위하여 하는 행동을 의미합니다. 스파이들이 은폐 중에는 공격을 할 수 없고, 전자 교란기를 은폐를 해제한 뒤 바로 설치하거나 공격할 수 없고, 뒤에서 공격하는 것으로 플레이어를 한방에 사살할 수 있다는 것을 기억해야 합니다. 스파이 체킹은 데드 링어를 장비한 스파이들은 재빠른 탈출이 가능하므로 이 체킹 과정을 더 힘들게 합니다.

스파이 확인

기본 전술

적 팀끼리는 서로를 뚫고 지나갈 수 없다는 것을 기억하십시오. 팀원과 부딫힐 경우 그 팀원이 스파이임을 알 수 있습니다.

약간 이상하게 행동하는 팀원을 주시하십시오. 비정상적인 장소나, 틀린 방향으로 이동하거나. 팀원과의 접촉을 피하거나 구석에 숨어 있는 아군에게 스파이 체킹을 가하세요.

적군이 있음에도 무기를 사격하지 않는 팀원이나 부상을 당했을 시 부활 지점으로 재보급을 하러 가는 아군을 관찰하십시오. 스파이들은 변장을 해제하지 않는 이상 무기를 사격할 수 없으며 변장을 했을지라도 아군의 리스폰 지점에는 들어갈 수 없습니다.

채팅창을 주시하십시오. 스파이들은 음성 명령을 사용할 때가 있는데, 이 명령은 스파이가 변장한 팀원의 이름으로 채팅창에 나타납니다. 자신은 말하지 않았는데 자신의 이름으로 나온 음성 커맨드가 있을 경우 적 스파이가 당신으로 변장한 가능성이 있습니다.

팀 색깔의 빛을 내는 연막이 있는지 관찰하십시오. 스파이들은 변장 도구로 변장할 때 이러한 효과를 내며 변장합니다. 스파이가 은폐한 상태에서 변장할 경우 이 연막은 나타나지 않지만. 은폐 전에 변장했을 경우 짧은 시간동안 이 연막 효과가 나타나게 될 것입니다.

사망했을 때, 부활을 기다리는 동안 맵의 관전자용 카메라를 이용해 맵을 다양한 각도에서 관찰할 수 있습니다. 은폐를 풀거나 변장하는 적 스파이를 찾았다면 그 스파이를 마지막으로 본 장소에 가서 스파이 체킹을 하십시오.

병과별 전략

스카웃

스카웃은 가장 빠른 클래스로, 팀원들과 항상 부딫히려 하는 것도 효과적인 전술이 될 수 있습니다. 위에 명시된 것처럼 적 플레이어는 지나갈 수 없고 부딪히게 되기 때문입니다.

샌드맨을 장착하고 팀원들을 기절시켜 보십시오. 샌드맨의 야구공은 팀원에게 맞지 않지만 변장한 적 스파이라면 기절시킬 수 있습니다.

미치광이 우유를 팀원에게 던져 입자 효과가 나타나는지 확인하세요. 자라테도 이와 같은 방법으로 사용됩니다.

스캐터건, 자연에 섭리, 유격수로 근접한 상태에서 2번 피해를 주기만 해도 데드 링어를 장착하지 않은 스파이를 충분히 사살할 수 있습니다.

플레이어가 지팡이 사탕, 놀랠 노자 또는 Unarmed Combat/비무장 전투를 장비하고 있을 경우 데드 링어를 사용하는 스파이들을 확인하기 쉽습니다. 데드 링어를 발동시킨 것은 사살이 아니기 때문에 각각의 아이템 효과인 치료제의 생성, 물고기로 처치, 팔뚝으로 처치가 발휘되지 않기 때문입니다.

포장지 암살자의 공에 맞아서 출혈하는 팀원들은 적의 스파이입니다.

솔저

팀원들에게 직격탄을 발사하여 터지는 지 확인하여 보십시오. 아군에게는 투사체가 그냥 지나가겠지만 적이라면 그렇지 않을 것입니다. 하지만 이런 방식으로는 탄약을 빨리 소모할 수 있으니 주의해야 합니다.

사기 증진 깃발, 부대 지원 그리고 전복자는 적 플레이어에게 영향을 주지 않으므로 이러한 무기들을 발동 시 주변의 팀원들 발 밑에 아군 팀의 색깔을 띤 원을 뿜어내는 입자 효과가 있는지 확인하여 보십시오.

적 스파이를 징계 조치로 후릴 경우 당신과 적 둘 다 속도 증진이 없습니다.

반쯤 자토이치로 데드 링어를 발동시킨 스파이를 사살하면 무기를 바꿀 수 있지만 체력이 회복되지 않습니다. 주변을 관찰하고 샷건이나 로켓을 발사하여 적 스파이를 찾아 보십시오.

파이로

파이로의 적을 불을 붙일 수 있는 능력은 스파이를 감지하는 데 가장 유용합니다. 특히 불타고 있는 은폐하거나 변장한 스파이들은 적 팀의 색깔의 빛을 띱니다. 하지만 이런 방식으로 스파이 체킹을 할려면 많은 탄약을 요구하고, 스파이 고드름을 장착한 스파이들에게 이 방식은 비효율적입니다. 이러한 스파이들은 체킹한 후 도망치려 하므로 쫒아가서 다시 불이 붙는 지 확인하여 보십시오. 스파이 고드름은 15초의 재충전 시간이 필요합니다.

압축 블래스트는 목표를 방어하고 스파이를 찾아낼 수 있는 매우 효율적인 방법입니다. 팀원에게는 넉백 효과를 주지 않기 때문에 넉백 효과를 받는 팀원은 스파이입니다. 하지만 압축 블래스트는 많은 탄약을 소비하므로, 건물이나 팀원들이 위험해질 위기에 처했을 경우에만 사용하도록 하십시오.

불타는 스파이가 데드 링어를 사용하면 화상 데미지로 인하여 바로 발동됩니다. 주변에 불을 뿌려대면서 가짜 죽음을 발동시킨 스파이를 찾으십시오. 그들이 죽었다는 확신이 설 때까지 추격하십시오.

전원 잭은 데드 링어를 발동시킨 스파이를 사살할 경우 체력 회복이 되지 않습니다. 적 스파이를 추격하여 사살하십시오.

데모맨

근접전에서 근접 무기가 가장 좋은 선택입니다. 가장 효율적인 방법으로 울라풀 막대가 있는데, 변장한 적 스파이를 가격할 경우 터지고 아군에게는 폭발하지 않는 점을 이용한 것입니다. 하지만 폭발 시 자신도 100만큼의 피해를 입는다는 것을 잊지 마십시오.

좁은 길목에서의 유탄 발사기에서 발사된 유탄들은 스파이를 구역 내에서 몰아내거나 폭발 피해로 눈에 띄게 되는 것을 감수해야 하게 합니다. 이 전략은 스파이의 투명화 에너지가 낮을 경우 스파이가 은폐를 풀도록 합니다.

점착 폭탄 발사기의 점착 폭탄 함정들은 스파이들이 저 지뢰밭을 건너는 것을 다시 생각하도록 할 것입니다.
돌격 방패 또는 경이로운 차폐막으로 하는 돌격은 변장한 스파이와 부딪힐 경우 끝날 것입니다.

반맹인검객으로 데드 링어를 발동한 스파이를 사살할 경우 무기를 바꿀 수는 있지만 체력 회복은 되지 않습니다. 주변을 조심하고 지역에 유탄을 뿌려대십시오.

망토와 단검을 사용하는 스파이들은 그들의 이동 경로에 점착 폭탄을 설치함으로써 쫒아낼 수 있습니다.

헤비

헤비들은 수상한 아군에게 미니건을 사격하여 스파이 체킹이 가능하지만 잔여 탄약에 항상 주의하십시오.

떨어져 있는 샌드비치를 부상당하지 않는 팀원이 먹었다면 스파이입니다.

미니건을 회전시키는 헤비는 스파이의 좋은 목표가 되지만 이 점을 역이용하여 스파이를 유인할 수도 있습니다.
- 화룡표 발열기는 스파이들이 화상에 대한 위험을 무릅쓰고 백스탭을 하도록 합니다.

화룡표 발열기를 회전시키는 중 근접한 팀원이 불이 붙을 경우 변장한 스파이입니다.

헤비들은 대부분 메딕과 함께 다니기 때문에 스파이들은 메딕을 죽여 팀의 치료원을 끊어버린 뒤 환자를 죽이려 합니다. 메딕의 뒤를 봐주십시오.

스파이가 한방의 미니건 탄환에 나가떨어질 경우 데드 링어일 수도 있으므로 주변에 총알을 분사하여 스파이를 찾으십시오.

데드 링어를 발동시키는 사살은 K.G.B의 치명타 증진 효과를 발동시키지 않습니다.

생일빵에 뒤를 맞은 팀원이 웃음 도발을 한다면 변장한 스파이입니다.

엔지니어

엔지니어로서 변장한 채로도 교란기를 설치할 수 있는 스파이들은 큰 위협입니다. 하지만 이러한 전술은 건물 주변에 아군을 둠으로써 방지할 수 있는데, 파이로가 이러한 일들에 적합합니다.

교란기 알림에 주의하십시오. 교란당한 건물 주변에 아군이 있을 경우 그 아군이 변장한 스파이일 수도 있습니다.

권총, 샷건, 또는 렌치로 다가오는 수상한 팀원들에게 스파이 체킹을 하십시오.

아군의 센트리 건이나 디스펜서를 지나갈 수 없는 플레이어들은 변장한 스파이와 그 건물을 지은 엔지니어밖에 없습니다.

긴 복도 끝에 랭글러로 조종되는 센트리 건은 총알과 로켓의 넉백을 이용하여 스파이를 쉽게 처단할 수 있습니다.

망토와 단검을 사용하는 스파이들을 찾기 위하여 주변 지역에 사격을 가하는 것도 좋은 방법입니다.

남부의 환영방식에 맞은 아군이 출혈한다면 적 스파이입니다. 출혈의 입자 효과는 스파이가 은폐를 쓸모없게 만듭니다.

과부 제조기는 적을 사격할 경우 금속을 회복하는 기능을 이용하여 최상의 스파이 체킹 무기가 될 수 있습니다.

메딕

As a Medic, Spies can use you to gain health while disguised. Both your primary weapon and melee weapon can Spy check easily.

Spies may target you while you are healing a patient. Watch your back while healing. You can also rely on your patient to Spy check; however, this could prove difficult during battle.

Spies may also simply head directly for your patient rather than yourself. Protect your patient, stop healing and quickly take out the Spy. You can also use the "Spy" voice command to alert them before they get close enough. If they do take out your Medic buddy, try to pedal backwards while firing Syringes to avoid being stabbed yourself.

Your Eternal Reward- or Wanga Prick-equipped Spies can stab your Medic buddy and will not interrupt your healing. If your Medic buddy suddenly acts suspicious, or if your teammate alerts you to the fact, take out your weapon and kill him.

When using the Crusader's Crossbow, it may be hard to Spy check. Spies will take damage from your arrows, instead of health. If a teammate is not being healed by your arrows (unless you are right next to your target), the player may be a Spy.

The Übersaw can be used on exposed Spies to gain some ÜberCharge. However, the longer swing speed may mean your life if the Spy is agile enough to circle around you.

When using the Amputator, your taunt heals teammates in close range. Any Spies disguised will not glow the usual team-colour during this taunt. Be wary, though, since you are vulnerable while taunting.

등가 교환 기나 탈출 계휙을 든 솔저를 치료 해보세요 만약 치료가된다면 그는 스파이입니다.

When enabled, the autocall for Medic option in the advanced menu only calls for a Medic if the Spy's disguise is low in health, while the "MEDIC" bubble appears red if the Spy himself is low in health. If you see a teammate calling for a Medic with a red "MEDIC" bubble, but his autocall Medic isn't ringing or his health is still good, he's a Spy.

스나이퍼

As a Sniper, your lack of mobility means you are an easy Spy target, especially while scoped-in. Use your SMG to shoot suspicious teammates around you, or douse them in Jarate.

Many Snipers only look ahead of them to discern any possible targets, and thus do not notice Spies beside them. Make sure to check your surroundings as you switch positions.

The Razorback may seem like the perfect anti-spy tool, but it is only really effective against Spies using the Your Eternal Reward (as they are unable to backstab you for a disguise), or the inexperienced and stupid. A competent Spy will just shoot you dead in 3 shots (or 2 if they are using the Ambassador or Enforcer), before you have time to react. Use other spychecking methods and be aware of your surroundings instead.

While using the Huntsman, an arrow will stick into a Spy, instead of going through them like it would toward a teammate. Use this to Spy check any teammates that are near you.

While the Kukri works well on killing Spies, the Tribalman's Shiv is more effective as the Spy will bleed, even while cloaked.

The Bushwacka is a good follow-up to a dousing of Jarate; the quick kill will make sure you won't be too distracted with hunting the Spy down.

If using the Machina, bring a weapon that can Spycheck well, such as the Tribalman's Shiv or SMG, as you cannot fire unscoped with the weapon.

스파이

The Spy can do a considerably good job of Spy checking. For example, your Knife, or its variants, can be used as an excellent screening tool; if you believe an ally is truly an enemy Spy in disguise, simply approach him/her from behind while your Knife is active. If you raise your Knife into the backstabbing position, you have effectively "seen through" the enemy's disguise. Spy checking someone who is actually a teammate will not yield this result.

If you suspect there is a Spy nearby, make use of the Dead Ringer. While active, the Dead Ringer can protect you from a backstab, while at the same time fooling the enemy into believing he has killed you. At this point, you can either rely on your team to kill the enemy Spy, reveal his location, or dispatch him yourself.

When facing a Spy using the Dead Ringer, remember that upon backstab, the Conniver's Kunai will not leech health, Your Eternal Reward and the Wanga Prick will neither disguise you nor dissolve the enemy's body, and the Big Earner will not grant Cloak.

If moving into an area not dominated by one team with the Cloak and Dagger, make sure that the corners do not contain other enemy cloaked Spies that might give away your position.

In Mann vs. Machine, The Spy can also use the Sapper to Spy check for Spy Robots. If the Sapper silhouette appears above the "teammate's" head, then they are a Spy Robot.

Revealing cloaked Spies

When cloaked, Spies will "flicker" their team color upon being damaged or when bumping into members of the opposite team. Keep an eye out for such flickering figures who appear in the opposite team's color. Try to strafe while navigating corridors in case a Spy is trying to go through that same corridor.
- The Dead Ringer does not have this drawback; however, it only lasts for the first 6.5 seconds of the Cloak, after which Spies will flicker when damaged or bumped into by members of the opposite team.
- Conversely, remember that friendly Spies will always be partially visible to teammates while cloaked.

Try to listen for the sounds of decloaking. Spies' cloaks will emit unique sounds when cloaking and decloaking, and such sounds indicate the presence of a Spy.

An Ammo box, Health kit, or a dropped weapon that disappears without a player walking over it indicates that it was picked up by a cloaked Spy. (Exception: if it was a dropped weapon, it may have simply disappeared because it was not picked up in time.) Spy check the immediate area to try to reveal the Spy.

In places with bodies of water, look for floating water drop particle effects. Players exiting bodies of water will be dripping with water, so any cloaked Spies that have recently exited a body of water can be easily identified by this.

An automatic door that suddenly opens without any visible player being nearby indicates a cloaked Spy passing through.

In general, weapons with a wide spread such as a Shotgun or Scattergun should be used to occasionally fire into corners where Spies using the Cloak and Dagger may be hiding.

As a Scout, try to throw Mad Milk into corners and crevices. It will immediately reveal any cloaked Spies and render their Cloak useless. The Scout's speed also allows players to patrol narrow corridors and bump into Spies attempting to make their way through side paths.

As a Pyro, try to randomly puff flames while patrolling, as there is always a chance that the flames will ignite a Spy trying to pass through. Puffing into corners and crevices will also usually uncover a Spy that is using the Cloak and Dagger and is waiting to recharge it. Beware that the Dead Ringer can put out flames if they are ignited, so if an ignited Spy suddenly drops dead, spray down the area with flames to ignite him again and use the compression blast to keep him at bay until the charge on his Dead Ringer runs out.

As a Heavy, spraying an area with the Minigun where a cloaked Spy may be can prove effective in exposing (and killing) him. The Minigun has a wide spread that can reveal Spies at long range.

As an Engineer, Spies can camp by Dispensers while cloaked for an unlimited time using the Invisibility Watch or Dead Ringer, or anywhere with the Cloak and Dagger. Try and check above and around friendly buildings to counter this.
- The Wrangler is also useful for spraying down areas, similar to how the Heavy can Spy check with the Minigun.

As a Sniper, similar to Scouts using Mad Milk, Jarate can short out an enemy Spy's Cloak, making him easy prey. Always try to throw Jarate into corners and crevices where Spies might be hiding before beginning sniping.

As with the Southern Hospitality, the Tribalman's Shiv can render a Spy's Cloak useless. Try to hit a Spy with at least one melee hit to reduce his chances of successfully escaping. However, if he has the Dead Ringer equipped, it will remove the Shiv's bleeding effect.

Protecting the Engineer's buildings

In general, simply try to Spy check anybody approaching a friendly Engineer's buildings. Spies trying to sap a building will usually make a bee-line towards the building they want to sap, so if possible, try to body-block the Spy to prevent him from placing a Sapper.

As a Pyro, use Dispensers to constantly refill the ammo of the primary weapon. This can be used to either create a standing firewall that Spies cannot pass through, or as periodic stops while constantly Spy checking the area.
- The Homewrecker or Maul can knock off enemy Electro Sappers with a single hit, while the Neon Annihilator can with two.

As a Demoman, the Stickybomb Launcher or Scottish Resistance is extremely effective at deterring enemy Spies. Simply place a few bombs around an Engineer's buildings and detonate them when the Engineer announces that his buildings are being sapped. While this may not be enough to prevent the buildings' destruction, it will at least prevent the Spy from escaping and causing more harm. It may also force the Spy to go completely around the buildings in fear of detonation by a watchful Demoman.

Similar to the Pyro, Heavies can use Dispensers to continuously refill their primary weapon's ammo, allowing players to Spy check over greater distances.

As an Engineer, always try to kill the Spy first before destroying any Electro Sappers placed on friendly buildings, as Spies will usually try to re-sap buildings immediately, or even try to kill the Engineer that is removing the Electro Sappers.
- If a Teleporter is being sapped from the Entrance, be sure not to stand on top of the Exit while destroying the Sapper; some Spies will deliberately try to telefrag players on the other side. Instead, stand next to the Teleporter Exit and melee the first person that teleports through, as it will likely be the Spy. If you want to repair your teleporter, stand near it and crouch. Furthermore, if the Spy does teleport through but dies on the first hit, he is likely using the Dead Ringer, so try to box him in and continue to attack to prevent him from escaping.

Identifying enemy Spies

Signs that definitely indicate an enemy Spy

Common signs

Various team-colored indicators will immediately give away an enemy Spy:
- The flicker of a Cloak from being bumped or injured.
- The fading of a Cloak while cloaking or uncloaking.
- The glow from being set on fire.
- The smoke from a recent use of the Disguise Kit.
- The cross from picking up a health kit.
A 'teammate' that asks for Medic and has "wrong" cross background colour. For example, Pyro at full health having its background red like on heavily injured teammates, or near-dead Heavy having it white.
A 'teammate' that cannot pass through another teammate, or conversely, a 'teammate' that has been observed walking through an enemy.
A 'teammate' whose weapons are not glowing and crackling with electricity when a team-wide crit boost occurs, e.g. after an Intelligence capture by your team. Keep in mind that some weapons are bugged and will not glow when crit boosted (like the Wrap Assassin), though they will still crackle.
A 'teammate' affected by another teammate's compression blast.
A 'teammate' that detonates friendly rockets and friendly grenades that have not bounced.
Seeing the cloaked silhouette of a non-Spy, or seeing a non-Spy cloaking or uncloaking. Friendly Spies always appear to be Spies, no matter their current disguise; any other cloaked class must be a disguised enemy Spy.
A 'teammate' who cannot enter a friendly resupply room, or who can enter the enemy's.
A 'teammate' that is somewhere where normal teammates couldn't be (e.g. near the enemy spawn at the start of the round).
A 'teammate' placing Sappers on friendly buildings.
A 'teammate' standing on a friendly Sentry Gun or Dispenser, or who cannot pass through them, unless it is the Engineer who owns the building. No other team member can collide with Sentry Guns or Dispensers.
Two people that have the same name. One (or both) of them is a Spy. (Players that join a server that has their name already in use by someone have a bracketed number appended to their name.)
Seeing or hearing a voice command attributed to you without having used it.
Hearing a teammate's voice command when there are no players visible nearby.
A non-Spy 'teammate' who picks up a health kit while at full health (unless it is a friendly Heavy replenishing his Sandvich or a burning or bleeding player healing the condition).
A teammate that is known to be dead or elsewhere, e.g. just respawned.
A teleporter that flashes but no one comes out, indicating an invisible enemy Spy came through.
A 'teammate' who has a name that does not correspond with his or her current class on the scoreboard. This happens when a Spy disguises as a class not currently on the team, or if the person has changed class while the Spy was disguised.
A player that triggers a voice response of "That Spy's an enemy!" or similar when they are targeted by a "Spy!" voice command and appear as another class (instead of being called out as "That Pyro's a Spy!" or similar). In addition, if the accuser appears to be a friendly player, both players are in fact enemy Spies.
A 'teammate' on an uncontested control point or near the cart on Payload maps who does not seem to be capping the point or pushing the cart (assuming the point is available for capture by that team).
A health or ammo pickup that vanishes without cause; this means a cloaked Spy has grabbed it.
A spurt of blood from nowhere accompanied by a cracking noise; this is probably a careless Spy that has just taken fall damage.
A 'teammate' holding a weapon they cannot have, such as a Sniper with the Razorback holding the SMG. This can occur when the Spy tries to switch to a weapon slot containing a passive item.
A microphone indicator that is not connected to a body on an alltalk server (cloaked Spies still display the team-colored '!' indicator).
A microphone indicator belonging to an opponent that is connected to a teammate on an alltalk server.
A 'teammate' that is using their microphone but has no corresponding microphone indicator.
A 'teammate' whose weapon sounds like the Revolver when reloading, making a single clicking sound.
A 'teammate' who is overhealed when there are no friendly Medics on the team (though there are various weapon-specific exceptions). This is caused by a bug which can assign (for example) the health of a Heavy to a Scout disguise, if there are no Scouts on the target team.
A non-Spy 'teammate' that is being ignored by an enemy Sentry Gun.
A non-Spy 'teammate' being healed by an enemy Medic or Dispenser.
A player on the humiliated team still holding their weapon.

Class- or item-based signs

A burning Pyro. Real Pyros cannot be ignited.
A friendly Engineer with the Hotrod flipped over his face, but is not holding a toolbox; this is an enemy Spy holding a Sapper.
A 'teammate' with the wrong movement speed:
- A Scout or Medic running slower than usual (not accounting for the Baby Face's Blaster).
- A low-health Soldier with the Escape Plan who isn't getting a speed boost.
- A Pyro using the Gas Jockey's Gear running at normal speed.
- A Demoman with the Scotsman's Skullcutter running at normal speed.
- A Heavy with the Gloves of Running Urgently running at normal speed.
A Soldier holding the Equalizer or Escape Plan and being healed by a Medic.
A Demoman holding an intact bottle or Ullapool Caber that has been previously seen as broken, and the Demoman is known to have not resupplied or respawned since.
A 'teammate' holding a weapon that cannot have yet recharged. Examples include Mad Milk, the Sandvich and Buffalo Steak Sandvich, and Jarate - if they have been used recently, seeing that player holding it again too soon indicates it is a Spy. But if they have +reload locked manually, via console command or some script, they actually MAY have this weapon still selected after use. For example, Scout may still hold Mad Milk after it's been used, but switching away to some weapon will disallow him to choose Mad Milk again until it's reloaded.
A 'teammate' that can be stunned with a friendly Sandman's baseball or bleeds from a friendly Wrap Assassin's bauble.
A stun graphic with no attached body; this is sure to be an unlucky invisible Spy struck by a friendly Sandman's baseball.
A 'teammate' that causes the Ullapool Caber to explode when struck.
A 'teammate' who is not healed by bolts from the Crusader's Crossbow; when real teammates are hit by a crossbow bolt, there is no impact sound.
A 'teammate' being affected by an enemy Medic's Amputator healing effect or, conversely, not being affected by a friendly Medic's Amputator.
The Medic's Amputator taunt buff appearing without a player, representing a cloaked enemy Spy.
A 'teammate' being soaked by friendly Jarate or Mad Milk, or not being affected by the enemy's.
A 'teammate' who appears unaffected by a friendly Disciplinary Action, and does not grant the Soldier a speed boost.
A 'teammate' who can switch from the Half-Zatoichi to another weapon without having made a kill.
A 'teammate' that laughs when punched with the Holiday Punch.
A piercing kill without an associated regular kill from the Machina, indicating a cloaked Spy was in the middle.
An enemy Scout or Pain Train user that is capping a point at x1 speed is a Spy disguised as one of his allies.

Signs that possibly indicate an enemy Spy

None of these indicators are conclusive proof of a Spy, but all of them would make a good time to run a Spy check:

Common signs

A teammate trying to stay behind other teammates, as if trying to backstab them.
A teammate not firing at the enemy.
A teammate who is in the direct firing line of an enemy but is not being fired at.
A teammate who retreats backward upon seeing other teammates, while still facing those teammates.
A teammate who appears to be dodging your team's attacks or backpedals immediately after seeing loose grenades or a carpet of friendly Stickybombs.
A teammate that deliberately avoids walking through other teammates, especially in tight corridors. Many Spies will strafe and dodge other players to avoid bumping into them.
A teammate that appears from a strange location like behind a rock or out of a dark area.
A teammate hanging around areas that are advantageous to Spies, e.g. nearby dark unnoticeable corners.
A teammate that can be seen taking a route but not exiting it or a different player exits it. This could be a Spy cloaking or changing disguises.
An apparently injured teammate running around the spawn area doing nothing or calling for a Medic, instead of getting health from the resupply.
A teammate that isn't displaying the player's usual mannerisms. Maybe a player always advances with their secondary weapon out, or spams the "Move up!" voice command, or jumps constantly - if they are seen doing otherwise, they may be a Spy.
Someone standing still at a distance from the rest of the team. This could be a Spy trying to line up an Ambassador headshot.
A teammate that appears to be looking more at your team than at the battle.
Being suddenly blocked for no apparent reason. This may indicate a Spy cloaked by the Dead Ringer passing through. Note that other possible reasons for being blocked include sudden periods of lag and unexpected map geometry.
A teammate calling for a Medic while at full health, who is not a Soldier, Demoman, or Heavy looking for overheal.
Anyone hovering near Sentry Guns or Dispensers, especially if they are attempting to move behind the Engineer tending them, or are at full health and do not seem to be collecting ammo.
Anyone running in an unexpected direction, such as a friendly Pyro, with full or nearly full health, running away from enemies.
Anyone who comes from an unexpected place, such as a Sniper coming down from the grate in 2Fort.
Someone acting inappropriately, such as a Pyro who stays near Snipers without lighting their arrows, a Demoman who is near a control point and has not placed Stickybombs, a Sniper at the front lines when the team is not advancing through a clear area, a Sniper near a control point or the Intelligence, etc.
A teammate that is going towards the friendly Intelligence room without a reason (usually only Spy-checking Pyros, Demomen with Stickybomb Launchers, Engineers, and players who are carrying the enemy Intelligence have a reason to go to the Intelligence room).
A teammate who takes unusual routes without reason, e.g. going through the gap behind the house on Dustbowl Stage 2 after the first point has been captured may suggest a Spy.
A teammate that doesn't switch weapons much or is holding a weapon that is not suitable for the situation, e.g. a Soldier with the Shovel out while pushing the Payload.
A series of dropped weapons or building gibs disappearing in staggered intervals. While they could be disappearing naturally, it's also possible a Spy is picking them up.
A player being attacked by real teammates who believe the player is a Spy.
A teammate who has not been observed shooting but is collecting ammo could be a Spy refilling his Cloak.
A teammate who someone else accuses of being a Spy.

Class- or item-based signs

A Scout that doesn't double-jump.
A teammate deliberately trying to avoid friendly Pyros.
A Pyro that doesn't Spy-check often.
A Medic who isn't healing anyone.
An Engineer or Homewrecker/Maul Pyro that doesn't appear to be attacking Sappers.
A Heavy that does not spin his primary weapon when enemies appear, or is not spinning his gun when standing next to a Dispenser with the team expecting an attack.
A low-health Heavy with the Sandvich out or equipped and is not eating it.
A Sniper who is not zoomed in.
Someone who hesitates before running past friendly Snipers with the Razorback.
An Engineer that does not appear to be upgrading or repairing his buildings (or helping others upgrade or repair theirs) when it is a good time to do so.
An Engineer holding the Wrangler without a Sentry Gun following his aim. Consider that the Engineer could just not have a Sentry built, or have a Sentry elsewhere.
A teammate holding a weapon you know they are not using, such as a Sniper holding the default Sniper Rifle when you know the player always uses the Huntsman.
A Spy near an enemy building but isn't sapping it.
A Spy near an important enemy (e.g. Medic with full Übercharge) but hasn't backstabbed him.
A Spy of your team's color wearing any mask. This either means that a friendly Spy is disguised as someone on the other team, or an enemy Spy is disguised as a Spy on your team.
A Soldier that doesn't rocket jump, even in situations when it may be helpful.

Signs that indicate a teammate is not an enemy Spy

These actions prove that a teammate is definitely not an enemy Spy. Performing any of these is a good way to inform your teammates that you are not an enemy Spy.

Common signs

Various team-colored indicators will immediately verify a friendly player:
- The near-transparent silhouette of a friendly Spy (invisible enemy Spies are impossible to see when undisturbed).
- The flicker of a Spy's Cloak from being bumped or injured.
- The fading of a Spy's Cloak while cloaking or uncloaking.
- The glow from being set on fire.
- The smoke from a recent use of the Disguise Kit.
Any usage of a weapon or item (shooting, swinging, eating, drinking, etc).
Can pass through teammates, as opposed to being stopped. (Beware that both such teammates may be, in fact, enemy Spies.)
A player entering a friendly resupply/respawn area.
Taunting (Disguised Spies cannot taunt).
If being fired at by enemies and is taking damage, e.g. bleeding.
Being able to pass through friendly buildings save for the Engineer who built them.
A player that is carrying the enemy team's Intelligence or capping a point for your team.
A friendly player who is using their microphone, whose voice icon is the same color as the friendly team: A symbol appears over the player's head. In servers with sv_alltalk enabled, the symbol is tinted red or blue according to the player's true team allegiance.
A player saying certain responses, such as an Engineer saying his buildings are being sapped.
A teammate being boosted by a friendly banner or Amputator taunt.
Any teammate dying and leaving a ragdoll of the friendly team's color.
A teammate that can be spectated. Note that some servers allow spectating enemy players.

Class- or item-based signs

Cannot be given negative status effects by friendly players, including afterburn, bleeding, stun, Jarate, and milk.
Any usage of class-specific abilities, e.g. Scouts double jumping, Heavies spinning their Minigun, Snipers that are scoped in, etc.
A Scout or Medic moving at his normal movement speed.
- A low-health Soldier with the Escape Plan, a Gas Jockey's Gear Pyro, or a G.R.U. Heavy moving faster, and a Demoman with the Scotsman's Skullcutter moving at a reduced speed.
A Scout under the effects of Bonk! Atomic Punch or Crit-a-Cola.
A Heavy under the effects of a Buffalo Steak Sandvich.
An Engineer holding a PDA or a toolbox (whether by preparing a building or hauling a building).
An Engineer who automatically calls out when his buildings are sapped or destroyed.
A Demoman's eye glowing from decapitating enemies with the Eyelander or any of its variants.
Does not cause the Ullapool Caber to detonate when struck.
A Soldier with an active banner flag on his back.
Spies with their Sapper or Disguise Kit out.
Spies without a mask on (not disguised) or disguised as a friendly player.
An Engineer Wrangling a Sentry Gun, provided the Sentry Gun's laser sight is visibly following the Engineer's aim.
A teammate who can be healed by the Crusader's Crossbow.
A friendly Soldier and a teammate receiving a speed boost when the former strikes the latter with the Disciplinary Action.

Specific anti-Spy strategies

본문: Anti-Spy strategy

Dealing with the Dead Ringer

The Spy has the ability to feign death with one of his unlockable items, the Dead Ringer, so always be wary upon killing enemy Spies as they may still be alive elsewhere. Thus, it's best to know some of the signs that tell that the Spy may not really be dead. Spies using the Dead Ringer cannot manually Cloak, and cannot use any weapons while the Dead Ringer is out.

If an enemy dies upon the first hit while approaching friendly lines without firing his weapon, it is most probably an enemy Spy disguised as one of his teammates. Most players don't run in with such low health, and a Spy disguised as a teammate will drop a corpse of the class he was disguised as.
- Similarly, if an obvious enemy Spy disguised as a teammate approaches the front lines from the enemy's position, he is most likely using the Dead Ringer, even if he doesn't die from the first hit. Remember that the Dead Ringer cannot Cloak at will, so a Dead Ringer Spy will rely on opponents' fire activating his feign death in order to become invisible.
- In general, if a player that has been identified to be an enemy Spy seems to be approaching a teammate suicidally, he is probably trying to get damaged so that his Dead Ringer will be activated, so don't be fooled.

A Spy must take the time to pull out his Dead Ringer before it becomes active, and cannot attack while he has it out. If a Spy suddenly stops attacking before dying on the next hit, he is probably using the Dead Ringer.

The decloaking sound of the Dead Ringer is highly distinctive, but requires players to be within a certain radius to hear it. Try to patrol near rarely-traversed areas to ambush a Spy decloaking in an area that he thinks is safe.

Picking up the Spy's dropped weapon does not replenish ammo or metal. This is an easy way to double-check if a recently-killed Spy is using the Dead Ringer or not.

Spies with the Dead Ringer will not flicker when damaged or walking into enemies while cloaked for the first 6.5 seconds of the Cloak, however, they still cannot be clipped through. Being stopped while moving and not bumping into any visible objects means that a Spy whose Dead Ringer was activated is trying to pass through.

If the Spy uses his Disguise Kit shortly before being "killed," the smoke effects will follow the Spy for the time that it takes for the Disguise to be equipped. Therefore, try to track any smoke that continues to move after an enemy Spy was killed.

When playing as an Engineer, if your Sentry Gun's kill counter does not increase after killing an enemy, he is probably a Spy. Remember that it may be hard to judge if the Spy was using the Dead Ringer since Sentry Guns will generally kill their targets very quickly.

When playing as a Pyro, even when the corpse drops after being ignited, the colored team glow will follow the Spy for a second. Use this to help alert others to the Spy, and to continue to chase and/or kill them. Jarate and Mad Milk also works in a similar way.

As a Pyro, the compression blast is the most useful tool for dealing with Dead Ringer Spies. After igniting a cloaked Dead Ringer Spy, simply push the Spy away from any ammo sources until the Cloak runs out.

By pressing tab, a player can view the scoreboard. In the bottom left of the scoreboard, you can view how many kills you have. You can check your kills after every kill, and if the kill count does not go up after "killing" someone, there is a Dead Ringer Spy around.

Dealing with the Cloak and Dagger

The Spy's Cloak and Dagger allows him to stay cloaked indefinitely, and to hide in unconventional places while waiting for the right time to strike. An area that may seem impossible for a Spy to hide in may be sheltering a particularly cunning Spy who knows where the enemy team will not check for Spies.

In general, most Cloak and Dagger Spies will try to hide in corners in order to avoid being bumped into as they recharge their Cloak. Try to occasionally fire into corners or vantage points with wide fields of view.

One brute-force method for dealing with the Cloak and Dagger is to simply repeatedly check an area where the Spy is hiding. As the Cloak and Dagger has an extremely short charge meter, the Spy cannot make too many movements or their Cloak will run out.

Some unconventional Spies will hide out in the open rather than against walls or in corners. This allows them to maneuver easily to avoid detection, and easily avoids the most often checked areas of a map. Try to keep this in mind if a Spy is suspected to be in the area.

Dealing with Your Eternal Reward

While Spies using Your Eternal Reward cannot use their Disguise Kit at will, they make up for this by being able to quietly Backstabbing any enemies and leaving no body for their teammates to find. A Spy using Your Eternal Reward can be impossible to detect even when he is killing teammates nearby.

Because they cannot use their Disguise Kit, simply identifying the last player that the Spy Backstabbed will let teammates know which player and class may be the Spy. Note that Spies with Your Eternal Reward equipped can still change their disguise weapon.

If backstabbed by the Spy, clearly announce this to teammates, as well as the class that the Spy is now disguised as, to make sure that they know who the Spy is disguised as.

The Spy's victims make no sound and leave no body behind to discover, but the body is still visible for a short time before disappearing. If players suddenly die noiselessly in the distance, it means that the Spy is there, so make sure to warn players as needed.

When the Spy Backstabs his victim, the faint sound of the melee hit can be heard if close enough. This can serve as a key warning that a Spy might be killing teammates in the immediate vicinity.

Remember that any kills made using Your Eternal Reward will not generate kill reports for the opposite team. Pay very close attention to teammates' movements and listen for any melee hit sounds nearby.

When a Spy with the Eternal Reward backstabs a teammate, the teammate's body disappears. However, their weapon remains sitting on the ground. If you see one of your teammates and their weapon on the ground, it's not a bad idea to Spy check him.