So is this just a thing where we guess what would "cards not in your hand" entail or do you have an explanation ready for that?

I think this is an 'un-set' card; mocking templating. And after all, Un did recently print 'infinity' as a power; so sure, why not? The actual number here is finite; although we don't know exactly what it is, it's gonna be big enough for any purpose.

Saying that - infinite toughness as well makes this better than the existing elemental; and so it need a significant up-cost.

I should actually limit those to the ones in your game...

This will get an upcost

This is still always going to be (60 - at most 7) * number of players.

So it's a minimum of 100/100. Even in limited it's 60/60.

Which is fine for an un card; but yeah, needs an upcost.

I put it to 6. Because infinity elemental cost 7. This is infinitely worse, but still great.

If it's still too cheap, I could make it more green-heavy. 3ggg maybe? Or i could put it up to 7 or higher. But i don't know why this would cost more than an infinity elemental

Oh; I love pointing out the "infinitely worse" part. That should totally be the flavour text :)

The main reason why this is better is that Infinity Elemental only has toughness 5. So while it's a terrifying threat, it's one that can be dealt with. This also has infinite toughness (not really, but big enough) which means that only flat 'destroy target' can deal with it. Which is a big thing, it basically means have zero ways to deal with it ever, while is pretty limited and only can really hope to stop it.

Fair point. Will heavly increase cost