Tumarkin's Cacophonic Truesight

You target a creature through a piece of stained glass and speak a command, and the target must make a wisdom saving throw. On a failed save, the creature is blinded and deafened and takes 1d10 psychic damage, as all its senses are opened up to the full scope of manifold realities collapsed over and throughout this one. It sees directly into the far planes, and into the ether, shadowfell, and feywild; it sees other material planes; it sees this plane at other times across the vast expanse of history.

Note: this blindness and deafness ignores immunity, but creatures with truesight have advantage on wisdom saving throws against this spell.

At the end of each of the creature's turns, it must attempt to make a wisdom saving throw. On a failure, it remains blinded and deafened, and takes another 1d10 psychic damage.

On any successful save against this spell, the creature may choose either to shake off the effect, or to take control of it.

• If they choose to shake it off, the spell ends. If they were blinded or deafened by the spell, they are no longer blinded or deafened, and they do not take damage.
• If they choose to take control of the effect, they take no damage and are no longer blinded or deafened, and for the next round they have truesight to a range of 120 feet. You cannot willingly drop concentration while they control the effect, and you gain advantage on saving throws to maintain concentration.

While the creature has control of the effect, it still makes saving throws at the end of each of its turns. It has advantage on these saves, due to truesight. On a success, it may end the effect, ending its truesight and releasing your concentration; or it may continue to control the effect, maintaining truesight and holding your concentration. On a failure, it returns to the blinded and deafened state and takes 1d10 psychic damage.

When cast at higher levels, the spell deals an extra 1d10 damage on the turn it is cast per spell level over 3. It also deals an extra 1d10 damage per spell level over 3 on a creature that has taken control of the spell, each time it loses that control.