You are granted the ability to cast a perfect genjutsu of your design, capable of trapping anyone within either your field of vision or a large area the size of a small city. You are capable of altering a target's perception of time, capable of crafting whatever world you wish as in this genjutsu whatever you desire, happens with no effort on your part. You can do anything from fitting weeks of incredible pain, to crafting a perfect and complete life for your target that if you wish, they can experience in a mere second. You can choose whether they feel any effects of any kind, good or bad, when leaving the genjutsu. In this genjutsu you are god.
Project V17/Powers/Shardless/Eternal Mangekyō Sharingan Abilities/Mangekyō: Tsukuyomi
From Worm CYOA Wiki
Naimen no Fūkei
Something strange has happened with the chakra fruit’s consumption. Somewhere between your chakra, soul, and body your mind has manifested as something real, something that can be interacted directly with. You are able to directly interact effectively with everything from your mind, soul, chakra and so on, allowing you to freely modify every aspect of yourself and everything linked to you. Removing things, adding things, changing things, sealing them away are all in your ability. And most importantly you have complete and absolute control over this realm, able to change how time moves through here, change its size, how reality works and every and any other aspect as you are god in your mind. You can bring others' minds here by casting Tsukuyomi on them and you may grant them as much access as you wish, and they can freely alter themselves the way you can if you allow them. As this is a mental realm, you may use this realm to generate an infinite amount of Yin, that you can then transmute into any combination of Yin and Yang, granting you an infinite supply of chakra. As this is merely in your mind you cannot physically visit or take anything in, nor remove anything into the real world, unless you gain mastery of Yin-Yang Release.