Alternate Reality (5e Spell)
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|Casting time:||1 reaction, which you take at the end of another creature's turn you can see in range|
|Components:||V, S, M (an unmarked die cut from a gemstone worth at least 100gp)|
This is a Wild Magic Spell, which can only be chosen or cast by a spellcaster of the Wild Magic arcane tradition or sorcerer Wild Magic bloodline.
You tamper with an event from within the last couple of seconds, potentially changing the outcome. You cast this spell at the end of another creature's turn, after any other effects that apply at the end of its turn. Choose one attack roll, saving throw, or ability check that that creature made during that turn. Events are reset to the moment they made that roll. That creature makes that roll again, with the same modifiers as before, and gains your choice of either advantage or disadvantage on the reroll. All creatures involved remember how it played out before the spell was cast.
At both the beginning and end of your next turn, you gain one level of exhaustion, as the space-time continuum itself wreaks petty vengeance on you for your slight.