Bug Description
Exploiters are able to kill non-player characters by dealing damage to the humanoid from their client. To do this the clients player needs to be close enough to the non-player character to take over network ownership. Normally the death should not replicate to the server if the damage was dealt on the client.
This bug only occurs if the client has network ownership of the non-player character. This bug does happen 100% of the time.
To replicate this bug follow these steps…
1: Create a new place and put down two dummies
2: Call one of them “dummyOne” and the other “dummyTwo”
3: Put a script in dummyTwo with this line of code
script.Parent:WaitForChild("HumanoidRootPart"):SetNetworkOwner(nil)
4: Kill both dummies from the client then check the server. You will notice that dummyOne is dead but nothing has changed for dummyTwo.
Make sure you are close enough to the dummies that you have network ownership of them.
You can also take a copy of this place if you don’t want to make your own NPC Client Bug - Roblox