The Collector

The Collector =

Highwayman =

Man-at-Arms =

Vestal =

"The twisted faces of the damned, piled high, and cloaked in malice."

- The Ancestor

The Collector is an Eldritch/Human miniboss who has a 3%, 4%, or 5% chance, depending on difficulty, to spawn if your inventory is over 65% full. He carries a Puzzling Trapezohedron, a gem worth 3,500 gold, or one of three powerful unique trinkets: Dismas' Head, Barristan's Head, or Junia's Head. His main strength is the ability to create grotesque parodies of Highwaymen, Men-at-Arms, and Vestals (referred to as the Collected in this article).

Behavior
The Collector is guaranteed to use Collect Call on his first turn, spawning a combination of Collected Highwaymen, Collected Men-at-Arms, and Collected Vestals. There is a 3/7 (~43%) chance to spawn a Collected Highwayman, a 2/7 (~28.5%) chance for a Collected Man-at-Arms, and a 2/7 (~28.5%) chance for a Collected Vestal. Only one Vestal and Man-at-Arms can be alive at any time, while Highwaymen are limited to two.

The Collector has specific chances to use Collect Call the fewer other enemies there are:
 * He has a base 3x chance to use it if there are 2 Collected left.
 * The chance increases to 9x if there is 1 Collected left.
 * He is guaranteed to use it if there are no Collected Highwaymen, or if no Collected are left.

Aside from Collect Call, the Collector will also use Show Collection and Life Steal, with a slight bias towards Show Collection.

Collected Highwaymen have only one skill, Headhunt, which can target any position, with a 3x higher chance to target marked heroes.

The Collected Man-at-Arms can only use its guard skill, Head Games, if there is at least one other Collected alive aside from itself; it will almost always guard either the Collector or a Collected Highwayman. Head Games has a 2x chance to be used over Head Knocker, which has no biases towards targeting.

The Collected Vestal normally has a 2x chance for either its buff skill Headache or its stress attack Head Rush, and a 1x chance for its healing skill Headstrong. It has a significant bias to buff or heal the Collector, with 2x and 5x chances respectively. Otherwise, it will usually buff a Collected Highwayman (4x) or just use Head Rush.

Strategy
With only middling stun resistance and speed, you may have a chance to stun the Collector on the first round before he uses Collect Call and damage him significantly, or, if you're lucky, outright kill him.

The real danger of the fight is not the Collector himself, it's the Collected Highwaymen. Their high damage, crit chance, and ability to inflict bleed can mean disaster. The other Collected enemies may also be troublesome, especially in conjunction: the Collected Man-at-Arms can guard allies, as well as stun heroes; the Collected Vestal will heal, buff, and cause stress damage.

The real priority target is the Collector himself, ideally while stunning any Collected Highwaymen to avoid damage. Once the Collector dies, all the Collected die with him, so just rushing to defeat the Collector as soon as possible will also avoid any additional damage. The Collector cannot move himself back, so pulling him forward with skills like the Bounty Hunter's Come Hither or the Occultist's Daemon's Pull will easily bring him into targeting range for more damaging heroes whose range would otherwise be limited.

If a fast kill is infeasible, then at least try to kill extra Collected Highwayman as soon as possible. Having only one of each Collected lessens the danger of the fight significantly, since the Collected Highwayman's potential damage is so high.

Take extra care if the Collector ever uses Life Steal—it has a very high crit chance (higher than Headhunt), heals the Collector, and applies a short mark, which will almost certainly cause Collected Highwaymen to attack the target. Even though Headhunt does not do any extra damage to marked targets, the hero will likely be weakened already by the damage from Life Steal, making this attack a real danger.

Trinkets
There is a 3/4 chance of him dropping a Puzzling Trapezohedron and a 1/4 chance of him dropping one of the aforementioned Heads. A player can only have one of each trinket in their inventory, so when all the Head Trinkets are collected, The Collector will always and only drop Trapezohedrons.

Abilities
Apprentice =

Collected Vestal
Veteran =

Collected Vestal
Champion =

Trivia

 * The Collector was added in the Inhuman Bondage update, along with the Madman and Abomination.
 * The Collector is a reference to Hastur, otherwise known as The King in Yellow.
 * The Collector also bears a striking resemblance to the Bloodborne character Micolash, Host of the Nightmare, who also has a cage affixed to his head.
 * The cage that the Collector wears was once a common form of torture employed for prisoners and lunatics. Spikes could be outfitted to the bottom of the cage to inflict additional pain on a subject being tortured should they attempt to crane their heads in response to pain. Additionally, some models featured sharpened spikes or spurs that projected from the horizontal cross-bars of the cage into the mouth, whereupon they dug into the tongue if the victim attempted to speak and were often fitted onto those accused of heresy or witchcraft. A variant called a "scold's bridle" or "the branks" was even employed to silence and humiliate housewives between the 1500-1700's by means of a curb plate which projected into mouth and pressed down upon the top of the tongue, preventing speech.
 * The Collector's trinkets bear the predetermined names of the Highwayman (Dismas), Man-at-Arms (Barristan), and Vestal (Junia). This is especially evident for the Highwayman, since the one you start the game with is named Dismas.
 * The Collector is the most recognizable boss enemy in the game around game's global community due to his design.