I have a question for an upcoming game… I want to make a “Prison Shiv” game pass would that break the rules in any way?.. I have reviewed the terms and haven’t found any way so far but just to be safe I’m asking on the Dev Forums.
-It will do damage to an enemy player.
-Will make a stab or swoosh sound depending if the players hits the enemy.
-Going to be a game pass.
Thanks from John… 
How is that different then a small sword?
I don’t see any reason why it’d be against the rules.
I’m pretty sure it’s allowed, but I can see why you’re asking - the idea that you’re in prison for some crime then you’re stabbing people with makeshift tools sounds a bit violent when described, but in-game it’s just the same as people using small swords as C0_le said.
See thank you! You get why I asked I like how you think. And thanks from John. 
Well it’s more than a small sword I don’t want kids to make their own due to the fact it will be made out of parts you can find lying around.
I mean you can play the mad murder in your kitchen so…
When it comes to weapons used to kill players and environment such as NPCs and others, it is best to simply not go over the top. Roblox is a platform where you can develop games pretty much however you want but you have to keep in mind that the targeted audience is relatively young. For this reason Roblox have to protect itself and its users from overly gore-y games.
An example of this would be the war games, you have guns, knives, grenades, gas and pretty much anything you can think of. These weapons have the focus on taking out other players and then move on, but if you put too much focus into the “killing” part then you might run into some issues with moderation. As if you were to make it so that you run up with the shiv, cut someone’s throat open and just do it as over the top as you possibly can, Roblox would most likely not approve.
Something else that is worth taking in mind is also, who are you using this tool on and for what purpose? If the shiv is used as just a regular weapon fighting something that can escape or fight back then that is fine. But if you use it as a way to torture or simulate the scenario of inflicting pain on someone/something then that will be moderated, and this more or less goes without a saying.
An example of this would be that “Ro-Bio” game or whatever it was called where you would have inmates that you injected with viruses that had a bunch of random effects as the inmates said things like “why are you doing this to me?” and “I only did a petty crime! I don’t deserve this!”. The concept of injecting others with viruses could be a fun thing to use in games if you made it so that it was some sort of a death effect for being stabbed by another player, it doesn’t necessarily have to be bad but in the case of this game, it was the use case. Clearly, this was just a game with the focus on torture, and thus Roblox took it down.
Pretty lengthy way to describe it, but I think you get the point. Weapons and such are fine, it entirely depends on the use case.