Case of the Locked Hothouse

Caso della Serra Serrata (Case of the Locked Hothouse) (it)

Enchantment - Case (CMC 4)
You may play an additional land on each of your turns.
To solve -- You control seven or more lands. (If unsolved, solve at the beginning of your end step.)
Solved -- You may look at the top card of your library any time, and you may play lands and cast creature and enchantment spells from the top of your library.