The equipment with the highest mana value is Excalibur, Sword of Eden with a big if in its clause: It costs significantly less for each historic permanent you control, meaning that artifact or legendary-themed decks can cast it for relatively free
What's the hold-up
If not, write "Needs work: Mechanical Issues" Is it written in the right style for MTG
I am a proponent of [card]Howling Mine[/card] effects in EDH, since it can take a glacial multiplayer game and cut an hour or two off the total
Rather, a second "reflexive" ability triggers when you sacrifice Eden, Seat of the Sanctum this way
While not directly involved with mutate, the ability is a great board wipe deterrent and removal deterrent, and if a mutated creature does die, I believe they all come back individually as flying creatures and that might be worse than a single mutated creature