Effect updates and description changes can be seen here.
Igloo was added in Beta 4.8 that, since Beta 48.0, allowed the user to see the 3 cards at the bottom of the enemy's deck. Not only that, they can also choose one of them and a copy of it will be added to their hand.
Due to it checking the bottom of their deck, not only does it help knowing what finishing cards the opponent has, but you can also combine it with Telescope when you want to copy a specific card.