It's kinda a pity that you can activate this any time there's an artifact out. It'd be nicer if we were still under 5th Edition rules so you could only activate this if an artifact was about to be destroyed. There's no sane way to word that these days though.

Not that you'd want to, but I think you could do:

"Exile ~ from your hand: Regenerate target artifact. When that artifact regenerates, put ~ into its owner's graveyard. At the beginning of the next cleanup step, if that artifact hasn't regenerated, return ~ to its owner's hand."

That does rather fail the "sane" requirement, though.

Dropped its P/T from 6/6 to 5/5 because I decided to standardise Gravecast - which now has you exile 2 cards from graveyard period rather than being a variable amount in addition to paying the Gravecast cost.
Having both the gravecast cost and number of cards exiled both variable was creating more confusion than it was worth, so I simplified it.

Hey! It's escape! Which incidentally does have a variable number of cards to exile.

Weird to see regenerate and landwalk around.