Oath of Scholars

1, T: Return target creature to its owner's hand unless its controller pays 1.

Shadow (This creature can block or be blocked by only creatures with shadow.) BB, Sacrifice this creature: Destroy target blocking creature.

At the beginning of each player's upkeep, that player chooses target player who has more life than they do and is their opponent. The first player may have this enchantment deal 1 damage to the second player.

Enchant creature Enchanted creature gets +2/+2 and can't block.

Enchant creature Enchanted creature gets +3/+3. When enchanted creature attacks or blocks, sacrifice this Aura at the beginning of the next cleanup step.

Flying U: Put this creature on top of its owner's library.

All damage that would be dealt this turn to target creature you control by a source of your choice is dealt to another target creature instead.

Each creature you control can block an additional creature each combat.