It'd grow ten times faster than any vulture ever, and healing is almost as common as creature death in the upped environment. Unupped, it'd be much less good, of course. Thing is, I don't think we can have an Immaterial growing creature. I don't see any way to balance that. Even with Permafrost, you can still pump out six of these babies and they'll be so much better than any Immortal/Phase Dragon it's not even funny.
Aye, I agree with you, in current environment with SoG spam, this would be a menace. But that is due to current metagame where SoG is stupidly strong card. It would be nice to get a direct counter to it, regardless if its this type of card or something else.
The issue I see here is that you yourself cannot set up Reaper to be any good. You can make a good use of Scavenger mechanic with silly stuff like Afla + Thunderstorm, Fractal Sparks etc. You can only HOPE your opponent has healing cards and will play them, if you take Reaper in the deck.
As it starts with 1 HP, the card itself is zero threat in current form. So, you're taking risk of guessing your opponent deck will heal, and your "counter" just dies the moment its placed down.
So, if you take away immaterial, either cost should be drastically lower, or its HP should be high enough to survive at least one CC.
