There's no reason why we can't make Mind Bomb cost or . It's probably too good at anyway. Round 1 Elite Vanguard, round 2 Giant Growth, swing for 5, then Mind Bomb for 5 cards sounds devastating (mana issues aside). Alternatively, we could just go with a set number... , sacrifice a creature, discard three cards sounds like a decent spell.

Reminds me of Death Bomb. Applying the conversions " instant Dark Banishing -> sorcery Mind Rot" suggests that would get 2 discards and 2 life. 3 discards is therefore probably reasonable but strong. Fugue / Mindstab were pretty backbreaking when they hit, so getting 1 mana discount on a Fugue may be definitely worth the loss of a creature.

If you want, you could also compare to Bog Down. Man, that thing was killer. I'd generally wait until round 4 or 5, then sacrifice two lands. Picking up the third card often meant the game.

Added to skeleton, upped cc and changed to 3 cards. For the record, the card original said "Target player discards X cards, where X is the sacrificed creature's power." I'm reluctant to change other people's cards, and probably would have left this alone, but I got a sneaking suspicion that, even if that card is fair (I think it is), it isn't quite a common... more something for uncommon. Jack may feel differently, though, so I'll leave the final question to him.

I'm fine with people changing my designs, since this is supposed to a community set, after all.

I think black is still in design, not really development yet, so I think this is your decision, but I think making something simple and common is the right way to go.

Also the name has to change