Inverted Reality

The Mangekyou Sharingan allows the user to shut down the enemies’ senses completely. They are able to invert the reality of the opponents by: creating the illusion that their attacks landed (even if it didn’t), making the ops think they are going to hit them on the left side, when in fact they hit them on the right side, and the opps would also feel the same injuries they receive during the fight (mostly internal); all of this can happen without the opps noticing their senses being shut down. The longer the fight, the crueler a death of the enemy would be.
Downsides of this is that the user, most of the time, gets gravely injured in order to end a fight quickly, and if they use it for a long period of time, their senses start getting confused as well.