Wrath of God

Destroy all creatures. They can't be regenerated.

Rith, the Awakener

Flying
Whenever Rith, the Awakener deals combat damage to a player, you may pay {2}{G}. If you do, choose a color, then create a 1/1 green Saproling creature token for each permanent of that color.

Nemata, Grove Guardian

{2}{G}: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Saproling creatures get +1/+1 until end of turn.

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

Birds of Paradise

Shivan Dragon

Flying
{R}: This creature gets +1/+0 until end of turn.

Sol Ring

Reconnaissance

{0}: Remove target attacking creature you control from combat and untap it. (If you activate during end of combat, the creature will untap after it deals combat damage.)

Squirrel Nest

Enchant land
Enchanted land has "{T}: Create a 1/1 green Squirrel creature token."

Earthcraft

Tap an untapped creature you control: Untap target basic land.

Viashivan Dragon

Flying
{R}: Viashivan Dragon gets +1/+0 until end of turn.
{G}: Viashivan Dragon gets +0/+1 until end of turn.

Flaming Gambit

Flaming Gambit deals X damage to target player or planeswalker. That player or that planeswalker's controller may choose a creature they control and have Flaming Gambit deal that damage to it instead.
Flashback {X}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.