What would you replace shellfighter with or is it required for this build?

It seems like the post pseudo-confirmed it

I only have one hydra, but I’ve been using the new 5/5 dragon that gives 3+ attack. Works pretty well in the deck!

I took out 2 wraithguards for 1 succubus and 1 prince malchezaar. Doing good so far, Malchezaar really helps with the 5 legendaries.

Replacement for thalnos? I know its good early game presence but I was think Rag for more of a late game.