Treadnaught

 is a boss found in the Black Powder Mine.

Behavior
Treadnaught moves towards the player, firing bullets from its corner turrets and occasionally its driver. In addition, Treadnaught has 5 special attacks:
 * Minion Bullet: Shoots out a bullet in the shape of a Bullet Kin that spawns a Tanker.
 * Exploding Bullet: Shoots a fast bullet that explodes when it comes into contact with an object and can destroy pillars.
 * Spreading Bullet: Shoots a rectangular bullet that splits into many scattered bullets.
 * Rocket Bullet: Fires a homing rocket bullet that bursts into a circle of bullets.
 * Pulse Bomb: Fires a large bomb-shaped bullet that releases bullets in small cones around the room and ends with bullets in all directions.

Strategy
The general strategy is to focus on taking down Tankers when they spawn and use the walls to provide some downtime while also letting it blow them up. Then, just kite around the entirety of the room and shoot it while avoiding his special attacks as they come out. If things get a bit too hairy, use a blank and immediately focus on any extra minions you see. To avoid its special attacks: Note that all the special attacks are negated if destroyed with Blasphemy except for Minion Bullet. However, you need good timing to destroy the special bullets.
 * Minion Bullet: Watch where the Tanker is landing and kill it instantly. Good ways to do this are a high fire rate gun or a full clip of pretty much any basic gun.
 * Exploding Bullet: Blowing up the pillars gives you more room to navigate around the room and lets you use long range weapons to hit his minions and the tank. Also, if you dodge roll when you're about to be hit by this missile, it'll knock you back without damaging you.
 * It may be beneficial to drop items that block bullets while remaining close to you, such as Sprun and Guon Stones, as they'll block the exploding bullet while it's close enough to you to damage you with its explosion, which can cause a very cheap hit.
 * Spreading Bullet: When you see it, just run sideways and you can dodge roll for extra safety.
 * Rocket Bullet: When it gets relatively close, run diagonally from it and dodge roll at the same time.
 * Pulse Bomb: Side step or dodge roll through the small waves of bullets as they come towards you. When the large wave explodes, dodge roll over and towards it to easily avoid it.

Treadnaught is incapable of moving in diagonal directions, so putting a good amount of diagonal length between you and Treadnaught can increase the amount of time it takes for it to reach you.

Trivia

 * If the player were to look at Treadnaught's boss card they could see a small face suggesting that it could be a mimic or be alive.