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.

Because exiling a card with foretell from your hand is a special action, you can do so any time you have priority during your turn, including in response to spells and abilities. Once you announce you’re taking the action, no other player can respond by trying to remove the card from your hand.

If you choose two target creatures and either target is an illegal target as Struggle for Skemfar tries to resolve, neither creature will deal or be dealt damage.

If the creature you control is an illegal target as Struggle for Skemfar tries to resolve, you won’t put a +1/+1 counter on it. If that creature is a legal target but the other creature isn’t, you’ll still put the +1/+1 counter on the creature you control.

If you’re casting a foretold card from exile for its foretell cost, you can’t choose to cast it for any other alternative costs. You can, however, pay additional costs, such as kicker costs. If the card has any mandatory additional costs, those must be paid to cast the spell.

You can cast Struggle for Skemfar targeting only a creature you control.