20/20 for 3 (x4)

Dark Depths enters with ten ice counters on it. : Remove an ice counter from Dark Depths. When Dark Depths has no ice counters on it, sacrifice it. If you do, create Marit Lage, a legendary 20/20 black Avatar creature token with flying and indestructible.

Enchant player At the beginning of enchanted player's first upkeep each turn, that player gets an additional upkeep step after this step.