Gatecrash

Crowned Ceratok | Creature | Rhino | Trample Each creature you control with a +1/+1 counter on it has trample. | Steve Prescott

Ivy Lane Denizen | Creature | Elf Warrior | Whenever another green creature enters the battlefield under your control, put a +1/+1 counter on target creature. | Winona Nelson

Ooze Flux | Enchantment | | {1}{G}, Remove one or more +1/+1 counters from among creatures you control: Create an X/X green Ooze creature token, where X is the number of +1/+1 counters removed this way. | Zoltan Boros

Scab-Clan Charger | Creature | Centaur Warrior | Bloodrush — {1}{G}, Discard Scab-Clan Charger: Target attacking creature gets +2/+4 until end of turn. | Nils Hamm

Fathom Mage | Creature | Human Wizard | Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.) Whenever a +1/+1 counter is put on Fathom Mage, you may draw a card. | Ryan Pancoast

Master Biomancer | Creature | Elf Wizard | Each other creature you control enters the battlefield with a number of additional +1/+1 counters on it equal to Master Biomancer's power and as a Mutant in addition to its other types. | Willian Murai

Unexpected Results | Sorcery | | Shuffle your library, then reveal the top card. If it's a nonland card, you may cast it without paying its mana cost. If it's a land card, you may put it onto the battlefield and return Unexpected Results to its owner's hand. | Mike Bierek

Ghor-Clan Rampager | Creature | Beast | Trample Bloodrush — {R}{G}, Discard Ghor-Clan Rampager: Target attacking creature gets +4/+4 and gains trample until end of turn. | Charles Urbach

Rubblebelt Raiders | Creature | Human Warrior | Whenever Rubblebelt Raiders attacks, put a +1/+1 counter on it for each attacking creature you control. | Chippy