Forbidden

Forbidden is a theoretical static ability which has been discussed by R&D, but has never been printed. It would alter the pre-game procedures by putting all cards with that keyword into exile, rather than the library, prior to shuffling and drawing opening hands.

Description
Forbidden was inspired by a custom deck made by Richard Garfield for spellslinging at the 2008 World Championships in Memphis, USA. He had "Gunk" cards in his deck, that didn't do anything and the means to transfer those cards to his opponent's deck.

Forbidden was created by Mark Rosewater for Avacyn Restored, and was flavorfully intended to capture the mystery of the contents of the Helvault.

Cards with forbidden would start the game in exile, similar to commanders starting the game in the command zone. Other cards would allow players to shuffle forbidden cards from exile into their library.

Forbidden did not playtest well, and was cut from the set during the "devign" step in the production process. It was replaced by miracle.

Despite its past failure, Rosewater still hopes to use the mechanic in a future set.