pokemon card seviper 132 [Colorless]. Seviper | Burning Shadows |

The IP itself is also incredibly popular

Its first attack, Backdraft, can deal 30 damage times the opponent's number of discarded basic energy , meaning it can deal immense damage to even powerful ex-cards

The green mana can be used for anything, letting you cast your noncreature spells, too, if you have any of those

Instant Kindred - Eldrazi Thief of Existence Devoid (This card has no color.) When you cast this spell, exile up to one target noncreature, nonland permanent an opponent controls with mana value 4 or less

In a cube setting it is pretty clear that you cannot have learn cards without lessons and the lessons are far too weak to bother including in a cube