Telshaz, the Night Stalker

First strike, Bloodthirst 3
When Telshaz, the Night Stalker comes into play, create a 3/3 black wolf creature token with first strike named Shadow.
As long as Shadow is in play, Telshaz, the Night Stalker has "Whenever Shadow and Telshaz, the Night Stalker attack at the same time, you may pay {x}. If you do, each opponent loses X life and you gain X life."