Inaros, Old Savior

Other creatures you control with a -1/-1 counter
on them have undying. Other creatures you
control with a +1/+1 counter on them have
persist. Other creatures you control with both counters on them have "{x}: Regenerate", where
X is their converted mana cost.
When Inaros dies, return it to the battlefield at
the beginning of the next end step. Then, Inaros
deals 2 damage to each planeswalker you don't
control.