Guilds of Ravnica

Affectionate Indrik | Creature | Beast | When Affectionate Indrik enters the battlefield, you may have it fight target creature you don't control. (Each deals damage equal to its power to the other.) | Steve Prescott

Vigorspore Wurm | Creature | Wurm | Undergrowth — When Vigorspore Wurm enters the battlefield, target creature gains vigilance and gets +X/+X until end of turn, where X is the number of creature cards in your graveyard. Vigorspore Wurm can't be blocked by more than one creature. | Jason Felix

Izoni, Thousand-Eyed | Legendary Creature | Elf Shaman | Undergrowth — When Izoni, Thousand-Eyed enters the battlefield, create a 1/1 black and green Insect creature token for each creature card in your graveyard. {B}{G}, Sacrifice another creature: You gain 1 life and draw a card. | Eric Deschamps