Oath of the Gatewatch

Meandering River enters the battlefield tapped. {T}: Add {W} or {U}.

Hissing Quagmire enters the battlefield tapped. {T}: Add {B} or {G}. {1}{B}{G}: Hissing Quagmire becomes a 2/2 black and green Elemental creature...

You gain life equal to target creature's power. The next time that creature would deal damage this turn, prevent that damage.

Equipped creature gets +1/+1 and has haste. Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Equipped creature gets +1/+1 for each other creature you control that shares a creature type with it. Equip {2}

Equipped creature gets +2/+2 and has menace. (It can't be blocked except by two or more creatures.) Equip {3}

Equipped creature gets +1/+0. Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Other creatures you control get +1/+0 as long as you control an Equipment.

{1}{R}{G}: Relentless Hunter gets +1/+1 and gains trample until end of turn.

{4}{G}{W}: Support 2. (Put a +1/+1 counter on each of up to two other target creatures.)

When Baloth Null enters the battlefield, return up to two target creature cards from your graveyard to your hand.

Devoid (This card has no color.) Flash (You may cast this spell any time you could cast an instant.) When Void Grafter enters the battlefield, anot...

Create two 2/2 white Knight Ally creature tokens.

Devoid (This card has no color.) Mindmelter can't be blocked. {3}{C}: Target opponent exiles a card from their hand. Activate only as a sorcery. ...

Target creature gets +1/+2 and gains reach until end of turn. Untap it. (A creature with reach can block creatures with flying.)

Vigilance, trample

Reach When Seed Guardian dies, create an X/X green Elemental creature token, where X is the number of creature cards in your graveyard.

When Saddleback Lagac enters the battlefield, support 2. (Put a +1/+1 counter on each of up to two other target creatures.)

When Loam Larva enters the battlefield, you may search your library for a basic land card, reveal it, then shuffle and put that card on top.

Support 2. (Put a +1/+1 counter on each of up to two target creatures.)

When Harvester Troll enters the battlefield, you may sacrifice a creature or land. If you do, put two +1/+1 counters on Harvester Troll.

Vigilance Land creatures you control have vigilance. Landfall — Whenever a land enters the battlefield under your control, you may have target la...

Target land you control becomes a 4/4 Elemental creature with haste until end of turn. It's still a land. It must be blocked this turn if able.