Mystic Reflection

If Mystic Reflection resolves, but the target creature leaves the battlefield before the next time one or more creatures or planeswalkers enter the battlefield, use the copiable values of the target creature as it last existed on the battlefield to determine what the entering permanents copy.

If a creature such as Clone is entering the battlefield under your control, there will be two copy effects to apply: the creature’s own and Mystic Reflection’s. No matter which order these effects are applied in, the creature will be a copy of the target creature when it enters the battlefield.

Casting a foretold card from exile follows the timing rules for that card. If you foretell an instant card, you can cast it as soon as the next player’s turn. In most cases, if you foretell a card that isn’t an instant (or doesn’t have flash), you’ll have to wait until your next turn to cast it.