Sorin, decisive kinslayer

: Whenever a vampire an opponent control dies, put a Loyalty counter on Sorin, decisive kinslayer
0: target non-vampire creature become a vampire in addition to its other types and get lifelink and haste until end of turn you gain 2 life
-7: destroy all vampires you don't control, then each other player loses twice X life where X is the number of vampires under your control