mtg forces of the imperium card list Collectors Edition - Warhammer 40,000 [40k] Premium Commander Deck 4 sided tokens Warhammer 40K Commander Decks Spoilers

In those do you want this over an Anthem

Tidus and the FFX Deck Tidus is a green, white and blue card with abilities that simulate the Sphere Grid by allowing you to place a counter on a creature you control

Not very much gets it out of play once there, it is in fact safer not turning into a creature

It reads: "Murktide Regent enters the battlefield with a +1/+1 counter on it for each instant and sorcery card exiled with it

On top of that, Ancient Cellarspawn itself makes Demons, Horrors, and Nightmares cost one less

Idris has all activated and triggered abilities of the exiled card and gets +X/+X, where X is the exiled card's mana value