Being a Lesson doesn't impact what the card does, but because it has that subtype, it can be cast for just one mana if you control Uncle Iroh, a Creature that makes your Lesson spells cost one mana less
If your commander isn't in the command zone (or you don't have a commander) as the last ability resolves, nothing happens
(Oh yeah, Unpredictable Cyclone doesn't care about normal timing restrictions, so you can use it to cast sorceries and creatures during your opponent's turn by cycling a card.) Eventually, this will give you an overwhelming amount of value thanks to all of the things you're playing for free with Unpredictable Cyclone and theoretically win you the game
This card feels poised to make a pretty big splashpun intendedand may even lead to a resurgence of merfolk decks in Modern and other formats
You need to convince your opponents that yes, you actually do need that Bolas's Citadel to save them and yes, you do need the Damnation in your graveyard to wipe the board
Note that you cant play lands that you exile off the top of your library, since the ability says cast, and lands are played, but you can still cast cards of any color