Copper Dragon's Trickery

You curse a foe with mishap, which strikes whenever it slips up. When you cast this spell, you can choose a creature you can see within range.

At any time before the spell ends, when you see the target make a melee attack, you can use your reaction to curse the first attack made by the creature. If this attack misses, then the target must succeed on a Dexterity saving throw or fall prone. It may attempt to stand up from the prone position at the start of its next turn.