Ah yes genjutsu. there are 10 applications in illusion manipulation
Afterimage creation: creating images moving at inhuman speeds
Altering Apperance: Changing your appearance to look like anouther person or whatever maybe even camouflage yourself
Death by Illusion :If the illusion is powerful enough, it can literally convince the brain to copy anything that happens to the victim within the illusion, making it possible to kill the target with illusions.
Illusion of Death. Making victim appear to be Dying over and over again
Decoy Creation:----> it explains itself OR you can go watch naruto
Holographic Projection: people that are acustom to light manipulation can create illlusions out of PURE light
Mazes: User creates a Maze depending on how powerful the user is, is what would determine how big the maze could be. it would also be possible to create " Moving Mazes and Never Ending Mazes
Pain illusion: ability to trick the human mind into thinking they are in Burning Pain. Has no Physical effect on the body has been described as feeling like you are being burned alive
Phobia Exploitation: makes a victims worst fears come to mind. can severely Scar a person in the head or possibly make them go insane
Sensory Overload: Target is forced with Overlapping Visions Causing Several Negative Symptoms
Torment Inducement: The user is able to induce and torture the victim's mind with tormenting illusions and thoughts from past, present and future It may be induce in all degrees of intensity, from mild to intolerance to physical suffering. These power is mostly used with illusions. The scale of this power can vary from a single person to a population, the time can also vary from few minutes to eternity. The user may also torment their victims mentally, emotionally, physical, and spiritually.
There are many Variations and Techniques. in other words you can target one person or if you are powerful enough you could affect a major population like a town or city