The target creature is automatically effected by this spell, there is no roll to hit & no save roll to defend it against this. The effected creature takes their next turn normally, however any actions they take upon that turn, they must repeat on the following turn. This includes movement, action, bonus action & any free actions. Note that the movement action will not be in the exact same direction on both turns, rather, on their second turn they will move in the direction of whoever they moved to the previous turn.

This spell has no effect on creatures who either do not have a mind or are incapable of acting with free will; for exmpale, a Golem has no mind & thusly is immune, additionally a thrall cannot act independently, instead they act only to do the bidding of their Vampiric lord & thusly is immune to this spell.

If for any reason they cannot repeat the action - i.e. the target they would've attacked is dead - then they are instead subject to the Stunned condition & may make a Wisdom saving throw against your spellsave DC to mitigate the Stunned condition.

A creature currently influenced by Yuan's Deja Vu may not be targeted by this spell again, until it has resolved.