Stalker

"I am your reckoning!"

- Stalker

Introduction
The Stalker is an ominous, vengeful figure that can infrequently appear during missions, armed with powerful weapons and abilities to hunt down the Tenno.

The Stalker wears Warframe armor and is able to use ability powers from various other Warframes, in addition to Dispel, which is his signature ability. His arsenal is similar to that of the Tenno, utilizing a primary, secondary, and melee weapon. The Stalker's signature weapons are the bow Dread, the scythe Hate, and the throwing knives Despair.

Spawning & Combat
Stalker can spawn in almost any player-accessible mission, including the Orokin Void. The only exceptions are Syndicate missions, Assassination missions, Relays, Dojos and The Law of Retribution[needs confirmation]. At least one squad member must be marked for death by Stalker before he will have a chance of spawning.

Upon being marked for death, the target Tenno will receive an in-game message from Stalker. After this message is received, the game will calculate Stalker's chance to spawn in a given mission according to the following formula: ""

When the game initiates a Stalker spawn, the targeted Tenno and the rest of their squad (if any) will experience flickering darkness, temporary deafness and unstable HUD. A transmission will open, taunting the targeted Tenno with threatening messages with what seems to be the shadow of the Stalker flickering behind the player. After three taunts, the tileset will enter lockdown, and Stalker will appear in a puff of black smoke before proceeding to attack the targeted player.

If the targeted Tenno is killed, the Stalker will kneel and vanish into another cloud of smoke, proclaiming his victory and that justice was served. If his health drops below 10% before he manages to kill his target, he will attempt to flee, announcing his shock at his failure, though he can still take damage and be killed up until he despawns.

If he is defeated (regardless of whether he fled or was killed), there is a chance for him to drop various loot items, such as a mod or a resource, or even blueprints for one of his weapons.

Audio

 * The Stalker's voice, used when taunting the players.
 * StalkerVoice.ogg
 * The Stalker's combat theme.
 * StalkerTheme.ogg

Taunts
One taunt is randomly chose from each group for each of the three taunts, in the following order:
 * Taunt 1
 * (Player's name), you can't run from your past.
 * (Player's name) there is no place to hide.
 * I know your every move (player's name).
 * Taunt 2
 * The blood of (boss' name) is on your hands. Did you really think there would be no repercussions?
 * The murder of (boss' name) will not go unpunished.
 * There is no salvation for your crime against (boss' name).
 * Taunt 3
 * You shall not leave this place!
 * I am your reckoning!
 * Your sentence is death!

Defeat

 * Player Defeated
 * (Player's name) shall not trouble us again.
 * It is done. (Player's name) is no more.
 * Justice is served. (Player's name) has been executed.
 * Stalker Defeated
 * What have you...done?
 * No?! This is not... possible.
 * I have failed. (Player's name) lives.
 * I... have failed... this one will remain... unpunished...

Miscellaneous

 * Your TENNO powers are useless!

Abilities
Stalker's signature ability, Dispel, negates all Warframe abilities used by players. As of Update 16, it has infinite range and zero cooldown. Stalker is also capable of utilizing the abilities of other Warframes, though it is not currently known exactly how many abilities he has access to. His most commonly observed abilities are Absorb, Pull, Shuriken, Slash Dash, and Teleport.

Strategy
Stalker is capable of dealing significant damage, comparable to a well-equipped Tenno, and can easily destroy an entire squad if they are caught unprepared. It is important to warn squad-mates when the Stalker begins his taunts so that they can prepare for the upcoming fight. It is also important to stay close to other squad members so that if he does manage to take his target down, the squad can revive them before they bleed out. Note that Stalker will despawn once the targeted player goes down, even if they are revived before completely bleeding out.

There are several ways to deal with Stalker once he spawns, such as constant movement, tanking, and / or fighting with melee weapons. Stalker will often use abilities from other Warframes, which should be avoided if it at all possible. Players should also remember that Stalker's signature Dispel ability will negate the abilities of all other Warframes, so relying on Iron Skin or Blessing to survive and / or attack is not an effective tactic. It is also helpful to switch to a melee weapon and block once Stalker appears, as this will give the rest of the squad enough time to locate and engage him while the targeted player is parrying his first few ranged or melee attacks.

If the targeted player attempts to run from Stalker, he will occasionally teleport behind them and engage in melee attacks, similar to the Grineer Flameblade. Stalker has also been known to Slash Dash towards a ranged target, dealing potentially lethal damage upon impact. He may also use Pull to drag his victim back towards him. When in melee combat, Stalker can stagger his taget by striking with Hate at just the right moment. He may also attempt to evade melee combat by back-flipping away from the engaging player. If Stalker's health gets too low, he can cast Absorb, forming a shield bubble around him which absorbs all incoming damage and explodes outward, dealing 100% of absorbed damage as Magnetic damage to players within range, draining their energy, and inflicting a Knockdown.

When actually fighting Stalker, it has been found that melee weapons are particularly useful, as Hate is less powerful than Dread and Despair, and both Dread and Despair can be blocked by parrying. In addition, having Reflection can reflect some of Stalker's damage back to him, largely eliminating the necessity of risking death in counterattacks with a player's own weapons. Do note, however, that the Hate staggers players who parry its blows, leaving you open to attack.

Short-range weapons such as beam weapons and shotguns are also highly effective; with the right weapons and mod configurations, many players can kill Stalker before he has a chance to attack.

It is critical to avoid firing on him when he casts Absorb, as the resulting explosion deals not only the ability's base damage, but also any damage the sphere takes before the explosion.

Other Notes:

 * Stalker typically only attacks his marked target, but he has been known to engage other party members if the target is out of range.
 * Stalker is completely immune to all Warframe abilities, regardless of whether they affect him directly or indirectly.
 * Some examples are Avalanche, Crush, and Miasma.
 * Dispel will negate all supportive abilities, such as Chaos or Ghost. It will also purge all extra buffs granted by abilities, such as the ferrite armor applied by Iron Skin, or damage resistance granted by Blessing.
 * Though extra buffs are purged, actions which modify existing stats (such as player shields and health) are still effective, such the shield and / or health effects of Blessing and Shield Polarize.
 * While Stalker can cast Dispel at will, there is usually a delay between casts in which certain abilities such as Decoy, Hysteria or Snow Globe may be used. The effectiveness of these abilities depends on how well players utilize them before they are dispelled.
 * Players may be able to avoid Stalker's attacks by keeping 50 meters of distance between the target and Stalker, but due to the frequency of his Teleport, this may be impossible to achieve.
 * It may be significantly harder for the targeted player to avoid or maintain distance from Stalker when they are the host of a multi-player session, as there is no latency while he targets the player and tracks their movements[needs confirmation].
 * When Stalker spawns, the current section of the tileset goes into lockdown. Depending on which tileset players are on, there is a possibility that it can be released by Hacking, either manually or with a Cipher.
 * If mission objectives are already complete, players can rush to extraction to complete the mission, avoiding having to fight Stalker entirely.

Trivia

 * The Stalker's taunt is actually played in reverse. The actual message heard is a long, drawn out message that simply and repeatedly says "Death" at varying speeds.
 * StalkerVoiceReverse.ogg


 * As of Update 7.11, the Stalker's loadout was altered to the weapons above. Before this update, his arsenal was comprised of a Cronus or a Scindo, and a Braton Vandal.
 * Prior to Update 9.6, the Stalker would not appear when the targeted player was standing on a crate. This has since been changed.
 * The Stalker appears to be wearing a dark-colored Excalibur suit, with a modified helmet.
 * It has been noted that the Stalker does, though rarely, exhibit much higher intelligence, performing wall runs, dive rolls, tracking cloaked players, and even actively avoiding enemies and other Tenno. It is unknown if this is due to certain rooms being designed for his AI, or reasons unknown.
 * As of Update 10.5.0, the Stalker has a new ability called Dispel.
 * The Stalker will toss his Despair in the air when in an unalerted status (usually caused by a bug).
 * If ever the Stalker appears and disappears in one of the victim's missions, his Combat Music will replace the conventional Combat Music for the rest of the mission.
 * The Stalker seems to spawn from inside of the cryopod in defense missions if the character he is targeting is somewhat near it or on top of the pod.
 * If a player is "taxied" (invited to a node/planet they have not unlocked) to a boss fight, they will not receive Stalker's mark for any boss fight they are taxied to as long as they have not unlocked the planet. If the planet is unlocked already but the node is not when the player is taxied, the boss node and those around it will be unlocked and all subsequent runs of the battle will not earn the player Stalker's mark so long as they are not hosting/playing the mission solo.
 * The Stalker can only be seen in the codex in the category all
 * You will not be marked for assassinating Captain Vor on Mercury, but you can get a death mark on Phobos. It is worth noting that Stalker's warning will first note Kril and then Vor.
 * You will not gain a death mark for assassinating Corrupted Vor, who is found in T4 missions.

Bugs

 * Stalker can be glitched by killing bosses like Captain Vor and Lieutenant Lech Kril and have him permanently after you, despite the number of times he kills you.
 * His captions also glitch as an indication when you glitch his targeting. It will say /Lotus/Language/Bosses/(Boss Name) instead of the actual boss name.
 * On rare occasions, the Stalker will glitch when he uses his cloaking ability, becoming permanently invincible to damage dealt by your team, being only damaged by enemies. This seems to be associated with the bug below as well.
 * Rarely, the Stalker can spawn in a defense mission, but replace the pod health bar with his own health. Even if the pod were to be destroyed as long as the Stalker remains alive, the mission continues. The Stalker then proceeds to attack enemies by itself. Once the Stalker gets downed, he can be revived normally just like a downed teammate.
 * When the Stalker is killed during a mission, the mission complete music is replaced with the Stalker theme. Same thing happens to the defense music, you will continually hear the Stalker music during a wave. After finishing the planet, it will return to the normal music.
 * There is a rare bug where the Stalker will be named after the respective boss of the area in his health meter. (i.e. Tyl Regor on Titania, Uranus, or Kela De Thaym on Merrow, Sedna). (Needs Confirmation)
 * There have been occasional encounters with level 1 Stalkers, perhaps due to host/client lag or glitches.
 * If the targeted Tenno is downed already before the Stalker spawned, the Stalker will freeze and become invincible.
 * The Stalker can appear in the Tutorial (if played again by more veteran players).
 * The Stalker can appear in the Mastery Rank tests.
 * Stalker may become permanently invulnerable after using his Absorb ability.
 * The Stalker may sometimes cast Absorb as soon as he is defeated. This will cause him to immediately disappear right as he finishes the ability. (The damage from Absorb will still trigger).
 * The Stalker can kill you while you are at the continue screen of defense and interception missions.
 * Sometimes, the Stalker may say that the player has killed a boss other than the most recent one killed (ex.The Stalker may state that the player has killed Lech Kril, despite the player not even having Kril's system unlocked).
 * The Stalker will sometimes taunt and attack players below Warframe rank 5 though this occurrence is extremely rare unless the player is in a lobby with another player who has the deathmark.
 * If the Stalker taunts you in a Rescue mission, his portrait may be replaced by the portrait of the hostage.
 * Sometimes, the Stalker's portrait may be replaced with the portrait of the Lotus.
 * Sometimes, the Stalker's portrait will have a black bar covering his face.

Stalker