The Angler resembles a heavily deformed anglerfish, with distorted features such as an open mouth that takes up the majority of its face. It has numerous sharp, thin teeth inside of its mouth and a third eye connected to its right eye. The Angler is constantly obscured by a thick dark blue smoke, obscuring everything aside from its face. Its face will constantly be facing the observer, no matter where they view it.
Mechanics
The Angler has a chance to spawn if the player's current or previous room has a valid hiding spot. When The Angler spawns, nearby lights will flicker briefly and The Angler will begin advancing. Once The Angler is close enough to the player it will start roaring, signaling for players to hide.
When The Angler rushes through the room, all players in its line of sight will be instantly killed. Players who hide in time or escape The Angler's line of sight before it passes through will be safe. The Angler's raycast goes towards the player's head, and will not kill anyone whose head is fully submerged.
Mirage
Rarely, instead of a regular spawn of The Angler, there is a chance for a mirage of The Angler to spawn. This mirage has nearly the same visual and audio cues (i.e., lights flickering, Angler sounds) as a regular Angler while not having an actual Angler attack. The mirage appears to be a faint, light blue cloud of gas. It does not break the lights like Pinkie and Pandemonium. The mirage's far and near sounds are identical to The Angler's underwater far and near sounds, which are muffled versions of The Angler's regular sound cues.
Notes
The Angler has a chance to attack from the front, arriving at the player's current room much faster. If it attacks in this way, the next door will automatically open and generate the next room once The Angler passes through it.
Only The Angler can attack from the front; none of its other variants can.
Anglers coming from the front cannot spawn on a timer, unlike other Angler variants and Pandemonium, and can only spawn when a player opens a door to the next room.
If a player opens the door to the next room after a front Angler light flicker, The Angler will teleport to the room that was opened. This can cause a near-instant death for the player entering the door, depending on the size of the room opened.
Anglers coming from the front cannot spawn upon opening a door to a room containing a keycard door leading to the next room.
After a player spends a set amount of time in a room, there is a chance for The Angler or any other node monster to spawn. This is called a timer spawn.
Before an Angler attack, the navi-path of the next door will flicker briefly. Knowing this makes it easier to tell when The Angler is coming into dark rooms or while passing through a room with Eyefestation.
The Angler cannot spawn when the furthest room opened is a dark room.
If The Angler, or any of its variations (aside from Pinkie), spawn while the player is in a bright room, they will break the lights in their path and convert the room into a dark room. When this happens, no further Anglers can spawn until another bright room is opened.
There are reports of Anglers spawning shortly after a door has opened to a dark room. This is assumed to be a bug, as Zeal has confirmed in the past that node monsters cannot spawn in dark rooms.[1]
The Ridge, while dark in many areas, is an exception to this and will continue to spawn The Angler.
The Angler will spawn extremely frequently in The Ridge, and will not be accompanied by any visual cues. Players are forced to rely on sound alone to know when The Angler is coming. The Angler's sound cues will happen earlier while attacking in the ridge to give players more time to react. Anglers coming from the front will not open the door to the next room.
Strategy
The best way to avoid The Angler is to hide in a locker before it rushes through the room you're currently in. Make sure to not hide too early, or you will be forced out of your locker due to cleithrophobia.
The Angler uses a raycasting hitbox to create its line of sight. Hiding in places that keep your character out of its line of sight by covering your character (such as side rooms, solid decorations, and vents) or by staying out of its range (such as hallways that lead away from the Navi-Path) will also work in evading The Angler.
The Angler shattering the electronics in the Oxygen Gardens.
The Pre-Friendly Fire version of the Angler.
The Angler shrouded in darkness.
The Angler traversing The Ridge with its eyes closed.
An early version of the Angler.
One of the oldest known depictions of the Angler in Pressure.
The Angler next to a scrapped monster, the Screamer.
An early version of the noises that the Angler emits.
Trivia
Multiple variants of The Angler can be encountered in-game. These include Froger, Chainsmoker, Pinkie, and Blitz. These are respectively referred to in documents as Z-283-Froger, Z-283-Chainsmoker, Z-283-Pinkie, and Z-283-Blitz.
The Angler was not executed while in Urbanshade's containment as it does not have a physical body and as such cannot be executed.[2]
Pandemonium is not part of the Angler family or Angler variant despite also being a node monster.
The Angler's design is loosely based on a deep sea anglerfish, hence its name.
The Angler does not have pronouns, as it was said that The Angler is "not a living being".[3]
The Angler lacks eyes in the Ridge.
The Angler's old design can still be seen in it's document.