Thee Mann, Dream Salesman

Eminence - If Thee Mann is your commander,
you may start the game with ten additional cards
in your command zone. If you do, for the rest of
the game, if a card you own would refer to a card
you own outside of the game, it refers to cards
you own in your command zone.
Any player may play noncommander cards from
your command zone. Whenever a player
casts a spell this way, put the top three cards of
their library into your command zone.