
Stormtide Leviathan | Creature | Leviathan | Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack. | Karl Kopinski

Sylvan Primordial | Creature | Avatar | Reach
When Sylvan Primordial enters, for each opponent, destroy target noncreature permanent that player controls. For each permanent destroyed this way, search your library for a Forest card and put that card onto the battlefield tapped. Then shuffle. | Stephan Martiniere

Ashen Rider | Creature | Archon | Flying
When Ashen Rider enters or dies, exile target permanent. | Chris Rahn