Fight is split in to 3 phases. In phases 1 and 2, attempt to finish with both of the adds in both faces having equally low hp (Phase changes as soon as one of them hits 25% and isnt casting anything) to ensure that when p3 happens, the boss has as small amount of health as possible (The bosses combine their remaining health).
2 tanks, 6-7 healers (2 on 10man, 3 if you really struggle in p3) and rest dps.
Phase 1 (Water/Fire adds)
Tank the mobs at where they are standing, just turn them around.
Split DPS rather evenly, with ranged on Feludius and melee on Ignacius.
Dispel the debuffs that can be dispelled (Not Waterlogged)
Feludius: Tank MUST interrupt Hydro Lance every time it casts (If he cant, assign a dps to do it), deals around 60-80k dmg on a random player if it goes through, if anything else hits at the same time, dead player.
When he casts glaciate, tank simply move a bit away and then back in, Hydro Lance also casts often after glaciate.
If you get hit by water bomb thingies and get the debuff, move quickly to the fire on ground and then back.
Ignacius: Tank facing away from raid.
When he casts Aegis of Flames, ALL dps switch to him and interrupt as soon as his shield drops.
When either one of the mobs hits 25%, phase 2 starts. Easiest way is to just get them both to <30 at ="25%,">
Source:wowhead
