Oh yeah, and when things go well, we can go infinite as early as Turn 3 or 4
Both of these cards are capable of doubling your mutate spells
Well, that and a lot of card selection
Ideally, you'd have fewer than four cards in your hand to gain some card advantage, but not so many fewer that you don't get a decent power boost for your creatures
One of Magic's best demons, Bloodletter of Aclazotz does a lot for your life drain shenanigans in any format
Indoraptor, the Perfect Hybrid The mana cost on Indoraptor, the Perfect Hybrid makes it a bit weird to fit into a Cube, but its reasonable to just slot it in as a Gruul or Rakdos card, and some Cubes just have space for gold oddballs