It doesn't inflict true physical damage (just mental), and the paralysis occurs if you manage to complete the illusion (i.e. the opponent doesn't deduce the fact that it's a genjutsu before the paralysis happens).
A-ranks! I'll give you all three of them in one shot. Is your body ready? xd
One handseal to place opponent in an illusion, then throw explosive tags at them, surrounding them. The opponent, under the illusion, sees the tags as butterflies. Then, they'll start sinking into the ground when they're actually immobile. Place one more tag on their forehead and release it, causing a large chain reaction of explosions that kills them.
Find me an image of this jutsu (in fact, do it for all three), and give me your opinion.
( Magen: Chō Shinka ) - Demonic Illusion: Butterfly Evolution
Rank: A
Type: Supplementary/Offensive
Range: Short-Mid
Chakra Cost: 30
Damage Points: 60
Description: The user makes one handseal, placing the opponent in a genjutsu. The user then tosses a large number of explosive tags at the opponent. To the opponent, it looks as if they are countless butterflies. The opponent then believes they are sinking into the ground, in reality making them immobilized; this allows the user to place one final exploding tag on their forehead before detonating all the tags simultaneously.
This one was used by Kabuto during the Chuunin Exams in Part 1. Great on multiple targets, though it takes effect after one turn.
( Nehan Shōja no Jutsu ) - Temple of Nirvana Technique
Rank: A
Type: Supplementary
Range: Short-Mid
Chakra Cost: 30
Damage Points: N/A
Description: The user makes one handseal, placing all the targets in the area under an illusion where feathers appear to fall from the sky. This slowly puts the opponents to sleep after one turn.
And the last standard genjutsu I can teach you is the famous Bringer-of-Darkness technique. Edo Hashirama used this against Hiruzen during the latter's fight with Orochimaru during the Chuunin Exams. I want you to describe how it works, and how/when you'd use it in a fight.
( Kokuangyo no Jutsu ) - Bringer-of-Darkness Technique
Rank: A
Type: Supplementary
Range: Short-Mid
Chakra Cost: 30
Damage Points: N/A
Description: The user makes one handseal, causing the opponent to believe they have been trapped in a world of infinite darkness, where their sense of sight is useless. It is capable of affecting multiple targets within range. However, it does not negate their other senses.