For 10 mana, you get a 12/12 with menace
Wrap Up Thief of Sanity | Illustration by Igor Kieryluk As you can see, there's a big gap between casting the spells for free or just having to spend mana on a stolen spell
Plus, you can give yourself an insured win condition by adding Halo Fountain from Streets of New Capenna if a Commander game goes on for too long
You can see gameplay footage of the deck from my stream and you can see it played in a recent Commander Clash
For instance, Arid Mesa can be sacrificed to search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle. While this can be used for basic lands of the stated types, it can also be used to fetch nonbasic lands with the given types
Each pair gets two Prerelease boxes, from which your team builds two decks