Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Berserkers' Onslaught

Attacking creatures you control have double strike.

Gratuitous Violence

If a creature you control would deal damage to a permanent or player, it deals double that damage instead.

Unnatural Growth

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

Bello, Bard of the Brambles

During your turn, each non-Equipment artifact and non-Aura enchantment you control with mana value 4 or greater is a 4/4 Elemental creature in addition to its other types and has indestructible, haste, and "Whenever this creature deals combat damage to a player, draw a card."