Sroller

It only exists during the lunar invasion that begins once the cultists outside the dungeon are dead, and only around the solar pillar. There is no summon item and no spawn outside that window, so every one you fight is part of clearing that pillar's shield.

Curling into a ball is not only how it travels. Balled up it soaks far more damage and hits far harder, so most of what you pour into the roll is wasted. Wait for it to open up and it dies quickly.

When the roll ends against a block it detonates, and the blast reaches well past the body. That is what catches players who thought they had dodged the charge itself. Give the wall it is heading for a wide berth.

The blast is not a projectile, which has one useful consequence for melee players here: it can be parried. Brand of the Inferno turns the explosion into a free counter, and Sergeant United Shield does the same. Anything else keyed to contact damage applies here too.

It looks four tiles tall but squeezes through a three tile gap, so a low corridor is not the barrier it appears to be. In water it stays curled and keeps coming at you, only unrolling once it touches solid ground again.