Doubling your life gain every since turn if yours is nasty, and if you have enough, you can turn it on your foes to kill them faster
You can also spend four, tap it, and Zombify a dork with haste from your graveyard and then exile it, and we don't have much recursion other than Volrath's Stronghold, so don't worry about the self-exiling much, when it's good, do it
The mechanic reminds me of Theros bestow, but with the ability to switch between modes at will
FAQ What are the most valuable cards in Lorwyn Eclipsed
The best token payoff cards in MTG are those that create more tokens, turn tokens into extra damage/cards, or help your wide board deal a lethal attack
#3 Find Out What Price You Should Be Paying In the advanced search select the sold listings checkbox and search for your desired set or card