Staggershock

Rebound found its most natural home on a burn spell, and this is the demonstration. Most rebound cards fight their own keyword: a draw spell or a combat trick wants its effect now, not on a delayed timer, so the exiled second cast arrives a turn after you needed it. A two-damage hit has no such complaint. Late is fine; there is almost always another small creature worth pointing at next turn, and four total damage adds up on a planeswalker or a face whether it lands now or a turn from now. The structure splits one card into two shocks on staggered timers, which lets a single spell answer two threats that show up a turn apart, something a one-shot burn spell cannot do without a second draw. The cost of that two-for-one is rebound's built-in friction. The front half is a reactive instant you can hold for the right moment, fired whenever you choose. The back half is committed and calendared: the card exiles on resolution, so you cannot bank the second copy, and the recast is bolted to your next upkeep, ignoring normal timing but arriving exactly when the schedule says rather than when you most want it. Two damage is unremarkable on its own. The design's trick is buying two of them on a stagger, with the deferred half costing nothing but patience.