Summon Marit Lage

Summon Marit Lage enters the battlefield with
10 summon counters on it.
Whenever a nontoken creature dies, remove a
summon counter from Summon Marit Lage.
Then when it has no summon counters on it, sacrifice it and create Marit Lage, a legendary
20/20 black Avatar creature token with flying and indestructible.
Sheoldred attempted to summon Lage and complete
her as a Phyrexian Avatar would make the Praetors unstoppable!