Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, Harsh Mentor deals 2 damage to that player.
Enchant playerAt the beginning of enchanted player's upkeep, that player sacrifices a creature or planeswalker of their choice. If the player can't, they lose 5 life.
FlyingWhenever you cycle or discard another card, put a -1/-1 counter on each creature your opponents control.Cycling (, Discard this card: Draw a card.)
Search your library for up to X basic land cards, where X is the number of tapped creatures you control, put those cards onto the battlefield tapped, then shuffle.
Flying, hasteYou may exert Glorybringer as it attacks. When you do, it deals 4 damage to target non-Dragon creature an opponent controls. (An exerted creature won't untap during your next untap step.)
Destroy all creatures with power 3 or greater.Aftermath (Cast this spell only from your graveyard. Then exile it.)Return all creature cards with power 2 or less from your graveyard to your hand.
FlyingWhenever you cycle or discard another card, put a -1/-1 counter on each creature your opponents control.Cycling (, Discard this card: Draw a card.)