The Destroyer

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The Destroyer is a Hardmode Boss, and is a harder version of the Eater of Worlds. Like the Eater of Worlds, The Destroyer is a very large Worm. Though it appears to be similarly made up of many segments, individual segments can not die, and The Destroyer will not split apart into multiple enemies. The entire enemy instead has a single shared Health, and will remain at full size until it is killed.

The Destroyer is summoned using a Mechanical Worm at Night. Night time is the only condition required for summoning. The Destroyer must be killed before dawn, otherwise it despawns. It can also spawn naturally as of 1.2 and spawns following the prompt 'You feel a quaking from deep underground...'. This change is a bit controversial though, since its entirely random and can come when a player is entirely unprepared, serving only to kill them.

Each of The Destroyer's segments contains a red-lit Probe, which are independent flying enemies that are launched periodically as The Destroyer takes damage. They fire lasers at the player, both while within The Destroyer and when detached. Probes can be killed individually. If the red light is missing from a segment, it means the Probe was already launched from that segment.

The Destroyer is immune to the Cursed Inferno debuff (however the probes are not).

Tips

 * The Destroyer is considered the easiest of the Hardmode bosses, despite it being the Hardmode version of the mid-difficulty Eater of Worlds. The Twins have a lower combined Health, but they can fly around with fewer movement constraints. Skeletron Prime also has less combined health, and only one part (his head) needs to be destroyed in order to beat him, but his arms constantly get in your way. However, if you are not good at dodging attacks, this boss can be troublesome, as it (as well as its probes) will shoot A LOT of lasers.
 * Out of the three Hardmode bosses, The Destroyer is the only one whose movement can be somewhat controlled. Being a worm-type, it needs blocks in order to maneuver, and can only launch above-ground for a limited height. For The Destroyer, that height can be sizable; around 3/4 of the screen (even in 1680x1050 resolution), but this weakness can still be exploited, for example by setting up a bridge of Wood Platforms high above the ground, preventing The Destroyer from reaching the player.
 * Consider using penetrating weapons, such as the Demon Scythe, Magical Harp, Golden Shower, Dao of Pow, Breaker Blade, Shadowbeam Staff, or even Boulders. Additionally using ammo like Meteor Shot, Hellfire Arrows, Jester's Arrows and Holy Arrows can deal damage to multiple parts causing major damage. Also the Star Cannon works amazingly well, if you have enough stars. The stars penetrate through his many layers, and do a nice amount of damage if you can coax The Destroyer in an upright position.
 * If you happen to have found the Rainbow Gun from the Dungeon, this boss becomes ridiculously easy. The only two problems with this strategy are the massive swarm of Probes (due to an insanely high DPS, although they get easily smashed by the Rainbow Gun as well) and the fact that it can be hard to control The Destroyer's moment of death, which may make it difficult to get his drops.