Altar of Kings

Build — 2
When Altar of Kings ETB, you may play a Hero card from your hand without paying its cost.
{t}: You may play target Hero card from your graveyard this turn if you pay {p/w}{p/g} equal
to the number of Revival counters on Altar of
Kings. That hero card enters the battlefield with suspend counters on it equal to the number of Revival counters on Altar of Kings.
Whenever Altar of Kings untaps, place a Revival counter on it.