Toil

If you're casting a split card with fuse from any zone other than your hand, you can't cast both halves. You'll only be able to cast one half or the other.

Some split cards with fuse have two halves that are both multicolored. That card is multicolored no matter which half is cast, or if both halves are cast. It's also multicolored while not on the stack.

If a player names a card, the player may name either half of a split card, but not both. A split card has the chosen name if one of its two names matches the chosen name.