"You will be cleansed..."
The Illuminant Master is a Hardmode boss. It is intended to be fought after the Mechanical Bosses and before Plantera.
The Illuminant Master does not spawn on its own, and requires the player to summon it with the Chaos Fire. Despite being a Hallow-themed boss, it can be fought anywhere. It must be fought at night time. Upon daytime, it will immediately despawn. When summoned, the screen will fade into a shade of magenta.
The Illuminant Master will teleport every few seconds, firing lasers at you. Every time it teleports, it leaves behind a ball of electricity where it once was, which explodes into 8 lasers. It will switch between teleporting into the ground and attacking you from below, and teleporting above you. When it teleports above you, it fires a spread of crystal spikes at you that deal lots of damage.
- The Master teleports below the ground and deals contact damage to you, firing no projectiles whatsoever. The ball of electricity it leaves behind is not usually a problem, as most of the time, it is too far away to hit you.
- The Master switches to teleporting above you, and firing crystal spikes each time it teleports. The ball of electricity now becomes a problem, as the lasers it explodes get closer.
- If you run directly into the Illuminant Master without touching its projectiles, its damage output will be extremely small.
- At half health, the Illuminant Master leaves a message saying "You will be cleansed..." and begins to fire a new type of projectile that deals enormous amounts of damage. All of its projectiles become much more powerful and the Illuminant Master fires a little bit faster.