Jeff, Keeper of A-Cores

Vigilance, Deathtouch, First Strike, Partner
All creatures able to block Jeff, Keeper of
A-Cores must do so.
Every time Jeff Keeper of A-Cores taps, create a
1/1 A-Core creature token.
{x}: Jeff, Keeper of A-Cores has reach and can
block X additional creatures until the end of
turn. Sacrifice X creatures: Jeff, Keeper of
A-Cores gets X +1/+0 until end of turn where X
is the combined power of creatures
sacrificed this way.