The tokens he gives (deathtouch, lifelink, hexproof, etc) work on anything, not just creatures. So if you activate an inkmoth nexus with Zetalpa in the yard, even when it reverts to a land it still has indestructible. And when it attacks, it's hitting with infect and doublestrike. Or if you gave Magus of the disk indestructible, you can use him every turn.
It works on other things too. For example, if you made Aetherflux Reservoir a creature and gave it lifelink, you'd end the game as soon as you reached 51 life.
I've been tinkering with him and he's a bit slow, so I thought I'd try him out with a bunch of boardwipes. I went a bit heavy with indestructible creatures so the devastation is one-sided. There's a couple flicker effects to reuse Kathril's etb ability, and lots of cards that put creatures in the yard while providing you with card draw.
Decklist
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