Does anyone have any tips for beating the eater of worlds in eternity mode. I am also running calamity in the same world.
For pure experience, try disable calamity mode
Otherwise,
1. Fight him on the surface; don't be afraid to leave the biome because in Emode, it no longer despawns when outside corruption. You can and you should build the arena much higher.
2. Get the iron enchantment; it is basically a better shield of cthulhu with a parry. In eternity mode, the vile spits cannot be destroyed, so when trying to change directions at the end of the arena, try to dash, and then parry in the air without losing momentum. That way, you can block most of the attacks plus, blocking the rotting debuff.
3. Place eater of souls banner in the arena to cover all the arena with the banner buff, and try focusing on the eater of souls first. It should always be your first focus, or otherwise the fireballs will swarm you to death.
4.Avoid touching the Eater of world itself and it's flamethrower at all costs. because of that, you might want to snipe the head. The destroy-stun-destroy strat no longer works, as of his flamethrower. 10 seconds of cursed inferno and 10 seconds of rotting can really mess you up.
5. Fight him in daylight. It's impossible to see the vile spits at night.