The curve is dangerously good with Llanowar Elves on turn 1, and Forest + Mossborn Hydra on turn 2
Leonardo, Sewer Samurai's base cost is one White mana and three colorless, but the sneak cost is two White mana and two colorless, so the overall amount doesn't change, but the structure does
Notably, this means other players can't try to remove Elves from the battlefield after you activate this ability but before it resolves
Cabal Coffers, the Tainted land cycle, Cabal Ritual, and Mutilate are all cards youve probably seen on the table during a Commander game
Cloaked creatures can be turned face up for their original casting cost, and since they dont change zones when you do so, you get to keep all their +1/+1 counters
Ignore any alternative costs or additional costs (such as kicker) paid when the creature was cast