Thornscape Familiar

Red spells and white spells you cast cost {1} less to cast.

Goblin Anarchomancer

Each spell you cast that's red or green costs {1} less to cast.

Target player can't play lands this turn.
Draw a card.

When Petravark enters, exile target land.
When Petravark leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Destroy target creature or land. It can't be regenerated.

Target player can't play lands this turn.
Draw a card at the beginning of the next turn's upkeep.

Destroy target land. If that land was nonbasic, Molten Rain deals 2 damage to the land's controller.