Colossus

Target creature gets +4/+2 and gains trample until end of turn.

Collision

Collision deals 6 damage to target creature with flying.

Collision // Colossus

Kessig Wolf Run

{T}: Add {C}.
{X}{R}{G}, {T}: Target creature gets +X/+0 and gains trample until end of turn.

Vedalken Heretic

Whenever this creature deals damage to an opponent, you may draw a card.

Ohran Viper

Whenever this creature deals combat damage to a creature, destroy that creature at end of combat.
Whenever this creature deals combat damage to a player, you may draw a card.

Xyris, the Writhing Storm

Flying
Whenever an opponent draws a card except the first one they draw in each of their draw steps, create a 1/1 green Snake creature token.
Whenever Xyris deals combat damage to a player, you and that player each draw that many cards.

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.