Therius, Swamp lord

: Whenever a creature you control dies, put 2 loyalty counters on Therius, Swamp Lord, and gain 2 life
-4: Destroy target creature, then search your library for a creature with the same or lower converted mana cost. put that crature into play
-8: Destroy all creatures. All players exile the top 20 cards of their library. Then, all players put the top threir cards of their library into play