Stealth

Stealth is the mechanic by which some units become invisible for a determined period of time.

Gameplay
Stealthed units will fade and/or disappear from enemy sight until they attack/have been attacked, or the duration of their invisibility effect expires. For ranged champions, auto attacks must actually land on a target for the stealth to expire prematurely. For some champions, using an ability that will cause them to become stealthed is preceded by a period called a "fade time", during which the champion appears partially transparent, but is still visible to enemies. During this fade time, any damage taken by the champion delays becoming invisible for a short period of time. No matter how many times a champion is hit, however, the fade time on invisibility cannot exceed five seconds depending on if the champion has base banshee's veil. Summoner spells can be used during stealth without breaking it.

Items

 * Wards from, and
 * Wards from, and
 * Wards from, and

Champions

 * will stealth her until the Twilight Shroud ends or Akali steps outside of Twilight Shroud. Whenever Akali casts an ability or autoattacks inside of Twilight Shroud, she is revealed for seconds. The Twilight Shroud also gives bonus armor and magic resistance for.
 * Evelynn stealths into the shadows only being seen by nearby enemy champions or true sight. While stealthed, Evelynn regenerates 1% of her maximum mana every second. Casting spells, taking damage or dealing damage reveals Evelynn for 6 seconds.
 * enters stealth for 1 second, gaining 40% bonus movement speed. Void Assault can be cast a second time within 10 seconds at no cost. If Kha'Zix evolves to have, he can stealth up to 3 times and takes 50% reduced damage while stealth.
 * stealths her instantly for seconds whenever she is brought below 40% health. When the stealth ends, she creates a clone of herself that deals no damage from autoattacks, and lasts for 8 seconds. This effect occurs almost instantly and can only work for once a minute.
 * gives him stealth over 7 seconds and reveals nearby champions. Rengar has movement speed bonus while stealthed.
 * will immediately stealth him for seconds and teleport him in medium distance. Note that he blinks after stealthing, thus the enemy team cannot estimate direction he went without stealth detection.
 * will stealth him for seconds and gives him 40% increased movement speed. If Talon breaks the stealth, The blades around Talon will converge and return to Talon, Dealing  damage to any unit they pass through.
 * will stealth him until he moves or attacks if stands still for 2 seconds. If he breaks the stealth, he gains 40% bonus attack speed for 3 seconds.
 * allows him to enter stealth after seconds of casting for  seconds. While stealthed, Twitch gains 20% movement speed. Upon exiting stealth, Twitch gains  bonus attack speed for 5 seconds.
 * gives her increased attack damage, a 1 second stealth after using and triple the bonus movement speed for.
 * will stealth him for seconds and leaves an uncontrollable decoy that deals  magic damage after  seconds.

Invisibility detection
There are various ways for a champion to gain the ability to see invisibility. A champion with this ability will see invisible enemy units as partially translucent. When a revealed invisible unit leaves the revealed area that unit does not experience a fade time; the unit immediately turns invisible again. The following is a list of possible ways to detect invisible Champions:

Items

 * , and : Legendary Items whose active covers an area with stealth-detecting mist for 6 seconds, granting vision of units which pass through it for 6 seconds. 60 second cooldown, 1000 Range, 375 AOE (estimate). Available in The Crystal Scar, The Twisted Treeline, and The Proving Grounds.
 * : A consumable potion (400g) was available at the item shop that granted invisibility detection to a champion for 4 minutes. Any invisible enemies enter this champion's vision range while this potion is active will be revealed. Used to be available on Summoner's Rift.
 * : A consumable potion (250g) that was designed for the game mode Dominion. Available at the item shop that grants invisibility detection to a champion for 5 minutes or until death. Any invisible enemies that enter this champion's vision range while this potion is active will be revealed. Available in The Crystal Scar, The Twisted Treeline, and The Proving Grounds.
 * : is a consumable item. When placed on the ground these stationary wards reveal an area of the map for three minutes. Any invisible enemy units within their vision radius during this time will be revealed. Only available on Summoner's Rift.

Champion abilities
The following abilities can reveal invisible units for a period of time:
 * , if her target stealths themselves during the channel
 * and
 * will reveal enemies if they stealth themselves while Pix is attached to them.
 * will provide semi-reveal. Though stealthed unit will still be immune to autoattacks and targeted spells, Duskbringer's trail will compromise the position of said unit for 5 seconds, even through movement.
 * causes struck enemies to leave behind a trail of blood even during stealth, similarly to Nocturne's aforementioned Duskbringer.
 * will reveal all enemy champions.
 * reveals all nearby enemy champions inside the ability radius.
 * will reveal all enemy champions.
 * reveals all nearby enemy champions inside the ability radius.

Turrets
Allied turrets have a "true sight" stealth detection range that will reveal any stealthed unit.

Presence detection without reveal
All abilities that do not require single target to cast can affect stealthed champions (but will not reveal them).

Certain abilities can only be cast if an enemy is in range of the AoE casting circle - these abilities will light up and become available to use even if the only enemy in range is a stealthed enemy.
 * can detect stealthed champions due to the particle effect pointing in their direction. The stealthed champion will not be revealed.
 * will explode but not reveal stealthed champions.
 * will follow a stealthed target and fire it's lightning bolts at it. The stealthed champion will not be revealed.
 * can detect stealthed champions due to the particle effect flying in their direction. The stealthed champion will not be revealed.
 * does not reveal stealthed champions but if they are within range and below half health, he will receive the movement speed bonus.
 * will explode but not reveal stealthed champions.
 * will follow a stealthed target and fire it's lightning bolts at it. The stealthed champion will not be revealed.
 * can detect stealthed champions due to the particle effect flying in their direction. The stealthed champion will not be revealed.
 * does not reveal stealthed champions but if they are within range and below half health, he will receive the movement speed bonus.
 * does not reveal stealthed champions but if they are within range and below half health, he will receive the movement speed bonus.

Skill shots
While skill shots that do damage and/or stun such as will still hit stealthed champions, they will still not be revealed. Note that the visible projectile will stop short of its trajectory and show visual and audio effects (eg. will make a splatter and show a small eruption of blood upon impact) if a stealthed unit is hit, indicating the stealthed champion's presence but not revealing them. Here are some more ways to detect stealthed enemies since they'll function the same as if they are unseen in brush.
 * will visibly entrap the stealthed champion without revealing the champion.
 * will visibly entrap the stealthed champion without revealing the champion.
 * will visibly entrap the stealthed champion without revealing the champion.
 * will visibly entrap the stealthed champion without revealing the champion.
 * can still missle lock on stealthed champions if hit with . You won't see the champion but you can see the debuff animation and follow it with your mouse.
 * Hook-type skillshots (,, and in some circumstances,  and  ) will show the effect of the hook happening without revealing the stealthed champion hit, revealing the champion's location.

Forcing enemies out of stealth
Taunting a stealthed enemy will cause him to attack, automatically revealing him and forcing him out of stealth. This can work if you target a visible stealthed unit or if the enemy is currently entering into stealth. With AoE taunts, such as or, this is easier as you can force every stealthed champion in the area to attack, even if they are invisible.

In the case of, skills which force him to move - such as , , , and knockbacks will also force him out of stealth.

Tarnung Stealth 潜行