Lynderika wrote:To be more specific, he doesn't turn into a rat, he always is.
that's not true, he starts as a clone at the beginning of the fight and turns into the rat after taking a small amount of damage. im guessing you probably start the fight with hades gate spam to clean up the adds and end up making him show himself every time
but yeah @OP just clear the boss room and hit the clones until one of them turns into a rat. if you have a curse it can help a lot with seeing him in rat form. another thing to keep in mind is that if he remains undamaged for some time he turns back into a clone i believe