Sorcery
Strive — This spell costs


more to cast for each target beyond the first.
Choose any number of target creatures you control. For each of them, create a token that's a copy of that creature, except it has haste. Exile those tokens at the beginning of the next end step.
If another creature becomes or enters the battlefield as a copy of the token, that creature will have haste, but you won't exile it. However, if Twinflame creates multiple tokens copying a single creature due to a replacement effect (like the one Doubling Season creates), you'll exile each of them.