Taigam, Ojutai Master

Casting the card again due to rebound's delayed triggered ability is optional. If you choose not to cast the card, or if you can't (perhaps because there are no legal targets available), the card will stay exiled. You won't get another chance to cast it on a future turn.

If Taigam leaves the battlefield after it attacks, its last ability won't trigger whenever you cast an instant or sorcery spell from your hand this turn. If it leaves the battlefield after the spell has gained rebound, that spell will still have rebound. Once the card is exiled, rebound's delayed triggered ability will trigger at the beginning of your next upkeep even if you no longer control Taigam.

If a spell moves itself into another zone as part of its resolution (as Teferi's Protection, All Suns' Dawn, and Beacon of Unrest do), rebound won't get a chance to apply.

If you cast a card from exile, it will go to its owner's graveyard when it resolves, fails to resolve, or is countered. It won't go back to exile.

If Taigam is killed in response to you casting a spell, the ability will still trigger and your spell will gain rebound if Taigam attacked.

If a replacement effect (such as the one created by Rest in Peace) would cause a spell with rebound that you cast from your hand to be put somewhere other than into your graveyard as it resolves, you can choose whether to apply the rebound effect or the other effect as the spell resolves.