To explore, you'll need to have a creature that can go on a journey and some card that causes it to explore (either as part of a spell effect, or an activated or triggered ability)
Vincent Valentine / Galian Beast Though it starts tiny, Vincent Valentine can be devastating when you combine it with removal spells like Sephiroth's Intervention
As utility lands go, theyre some of the best Magic: The Gathering has ever seen
Similarly, by the time Mortal Combat kicks into gear, I could have won the game elsewhere
Keyword soup aside, Lightning comes with the remarkable ability to double any damage youd deal to a player (or a permanent) that player controls until your next turn
The rest are narrow, powerful combo pieces like Earthcraft, Dream Halls, Fluctuator, and Recurring Nightmare