The Crusher shares most of it's AI with the other melee-based monsters, when aware of the player's presence, it will walk at the player & when within it's melee range, it will stop and begin it's attack animation. it currently has no other behaviours.
The most efficient way of dealing with crushers, taking into account ammo usage, is to strafe back and forth between their melee attacks, allowing an uninturrupted string of your own Hyperblade attacks, maximising DPS for no ammo usage whatsoever. Mastering this technique can be very useful for when you fight Crushers in close quater rooms, where you have little manuverability, as this technique should keep them pretty much in place, giving you maximum breathing room.
- The crusher is immune to infighting.