Doran, Besieged by Time (#334)

Type: Legendary Creature — Treefolk Druid

Text: Each creature spell you cast with toughness greater than its power costs {1} less to cast.
Whenever a creature you control attacks or blocks, it gets +X/+X until end of turn, where X is the difference between its power and toughness.

Set: Lorwyn Eclipsed (#334)