So, I've been talking to Sjlver lately. We've made the next set.
BIPRWB of OIBUWE
This set features 4 color "splotches." Each of these splotches is designed for fighting the color omitted. For example, the Blue Green White Red splotch, Blark, has creatures that have protection from creatures with Fear, Intimidation, and Deathtouch.
So, we also made up a new mechanic to go with this set. Playing 4 colors is hard, so we thought we'd make it easier. Also, we are dissatisfied with Morph. We felt that cards with morph weren't really worth it, and cards that revealed morphs were not really worth it. So we made a new mechanic: Rifts.
You put a card in an unstable time rift that is a 2/2 token. The card may be played (at instant speed), at it's CMC.
How is this different? Rift wouldn't be a creature ability. It would be a part of a sorcery or instant. Now, this has present a few problem. It was originally creatures, but you would have to make sure the thing is a creature, but to do so, you would have to reveal it. To avoid play errors and tomfoolery, we just made it any card.
Example card:
Temporal Wedge {B/U} {G/R}
Sorcery
Suspend 3
Return target permanent to its owner's hand.
Rift (Places a 2/2 Rift creature token onto the field with "{X}, Sacrifice this Rift: Play imprinted card, where X is the imprinted card's converted mana cost," then imprint a card onto it by exiling the card from your hand face down. You make look at the imprinted card.")