Travis, Shaman Of Wrath

Trample, haste
The first creature spell you cast each turn costs {x} less where X is the greatest power among creatures you control.
When Travis attacks, you may pay {2}{u}{r}{g}, if
you do, create X 2/2 Spirit tokens with "Sacrifice
this creature at the beginning of the end step"
tapped and attacking where X is the greatest
power among creatures you control.