Hypnotism could be an added skill, where anyone can attempt to hypnotize someone, but it depends on the skill. Resistance to hypnotism could be based on how crowded and/or noisy the place is, the victim's intelligence stat, and whether or not the victim was prepared for the hypnotism or they saw the hypnotist preparing to hypnotize them. To put the skill in check, I think still in addition to the other factors, to stop hypnotism from being too powerful, there should still be a certain sum of luck involved, and also the hypnotism gets less effective as time goes on, before it releases the victim at a maximum of maybe 45 min-1 hour after the hypnotism originally occurs. Also, the act of hypnotism should the only be allowed to be performed once a day or once every two days. If successfully hypnotized, the victim should still be able to try to resist, but their willpower gets weaker gradually over time, giving them less and less chance of breaking free. The intelligence stat can also be lowered for a temporary period of time after being hypnotized, the amount depending on the strength and length of hypnosis. Certain items can also be bought, like watches or swirls, possibly, to aid in hypnosis, though they should not be too powerful, and someone with no skill in hypnosis should not get a bonus from them. In addition, also, to manually typing in "resist" or something, the victim should automatically try to resist every time they try to perform an action- the chance of them breaking free, or at least staying hypnotized but stopping themselves from doing the action, would depend on the difficulty of the action. For example, ordering the victim to kill someone would yield a much higher chance of them breaking free than ordering them to walk down a street, or follow you. It's just an idea, but I thought I'd throw it out there.