The Dark One

The Dark One is a boss that is fought in the final room of The Darkness whose main gimmick is accumulating darkness enemies to limit the space of the boss arena.

Appearance
The Dark One is completely black in body color. It wears a dominus and has bat wings on its back.

Behavior
The Dark One will chase the nearest player, but copies 90% of the player with the highest. Every 10 seconds, it will summon other darkness enemies, limiting the space inside the arena even more. Alongside The Shadow, it will iterate between summoning The Phantom and The Corrupted, and speeds up the Shadows with each summon. It can only summon 10 before stopping.

Tips

 * It is recommended that ONLY the player with the highest battles The Dark One.
 * The reason for this is because it will switch to a different player to attack, switch again, and vice versa, catching players off-guard, which means that if someone else has a lower, they will die easily.
 * Make large and smooth turns around the room to prevent The Dark One from catching up.
 * Get other party members to stay in corners together, and work together to fight off any summons that come their way.
 * You should catch the aggression of all of The Dark One 's spawns immediately, as not doing so will set them up to cut you off when you circle back around. They will naturally cluster and get hit while you are fighting the boss.
 * As the boss is weak to, it is recommended to use a sword with that element. However, these swords do not appear until later in the game.
 * If you are playing as a class that takes advantage of large groups of enemies for stats and other benefits (such as Gardener), it is highly recommended to let The Dark One spawn all 20 of his minions in order to then utilize them.
 * It is recommended to warp back a few worlds in order to decrease The Dark One 's scaled, making him much easier to fight.
 * Kill The Dark One as fast as you can, otherwise his spawned Shadows will slowly accelerate in speed and eventually outrun you, ending your run.
 * If you obtained a Flashlight, use it for The Dark One as it can instantly kill it.
 * If the player is a and has either an Amethyst Sword or a Dicey Blade, they can do a darkness run relatively easily.

Trivia

 * The Dark One was the first boss added into the game.
 * The Dark One and the Xero Droid are the only enemies that can copy their target's.
 * The Dark One is the first enemy that can naturally spawn other enemies, not counting Droids with the Random modifier.
 * It does a special animation whenever it summons something, raising its arms in the air.
 * It is the only enemy that drops an exclusive evil item with that being Bat Wing.
 * It is immune to most items, spells and abilities, including Wrath (Sin), only being affected by weapons.
 * Its depends on the world The Darkness replaces.
 * After killing The Dark One, shopkeepers will be replaced by their hat which will be on the floor.
 * Entering The Darkness will change the death messages to be motivational instead of being sarcastic and set their color to red. Also the black text introducing you to the current world, along with it's name will be red. This applies even if the world is cursed or blessed by a modifier.
 * The Skipping Stone used to completely skip the entire boss fight.
 * The Dark One used to have no limit as to how many minions they could spawn, which could crash your game if you could not dish enough damage.
 * You can instantly kill The Dark One with a Flashlight, as it is vulnerable to.
 * The theme when fighting The Dark One is Ascension (Chest Fight) - The Binding of Isaac: Rebirth.