Thi-Grun, the Undying

Whenever Thi-Grun, the Undying dies, at the beginning of the next upkeep, return it to the battlefield with X plus one +1/+1 counters on it,
where X is the number of +1/+1 counters on
Thi-Grun when it died.
"Our greatest warrior, Thi-Grun has never failed to
stand back up after receiving a lethal blow. This is the
power of the Anserian Empire."
-Nadya, Anserian Empress