Mountain

Maelstrom Wanderer

Creatures you control have haste.
Cascade, cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order. Then do it again.)

Island

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Forest

Meandering Towershell

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Meandering Towershell attacks, exile it. Return it to the battlefield under your control tapped and attacking at the beginning of the declare attackers step on your next turn.

Worldfire

Exile all permanents. Exile all cards from all hands and graveyards. Each player's life total becomes 1.