Yaligo, Father of the Forest

This spell costs {x} less to cast where X is
The combined power of Elks you control.
Yaligo's power and toughness is equal to twice
the number of elks you control.
When you cast Yaligo create a number of 3/3
green and white Elk creature tokens equal to
Yaligo's power.
Other Elks you control get +2/+2 and trample.