Client To Server

     Take advantage of Roblox's RemoteEvents. Remote events send a request to the server that says, "Hey! I sent a request to you with some variables! Can you check it out?". The server then will execute whatever code there is after the event is fired. Most FE scripts take advantage of RemoteEvents.

     Some games are stupid and use a server-sided loadstring() backdoor that we can take advantage of to run code on the server:

game:GetService("ReplicatedStorage").ExecuteSSLua_orSomethingLikeThat:FireServer([[PUTYOURCODEHERE]]);

     There are some sources out there for finding RemoteEvents and taking action. One of them is FilterShark (You need a paid exploit to run.). You can also just use Dex Explorer and use your executor to do it (That will require some experience).

EDIT: Made more understandable.

Ive already got a working dex explorer, thanks for the help

@nicholash777 So one of the output from this has the fireserver property

Code i put in

@UnkownRobloxian

Bingo! You got it. Only the ones that are the instance class 'RemoteEvent' will work. Now you have to find out what values you have to put in for it to work. For example, If I had a script on the client that said Punch. I would probably do:

game:GetService("ReplicatedStorage").Punch:FireServer("VICTIM")

@nicholash777 so i just use the functions that are already there rather than putting in my own code? Struggling a bit trying to get it to work

@UnkownRobloxian

(Sry for the late reply.)

     You execute your code that has the :FireServer() in it, but the functions are server-sided. You have to experiment with what strings/values the RemoteEvent needs in order for it to do what you want. On the server, it might be ReplicatedStorage.Punch.OnServerEvent(player, strength). But you can't see that. So you might execute

Punch:FireServer(math.huge, "VICTIM"),

but it wouldn't work. So you flop it around and you get this:

game.ReplicatedStorage.Punch:FireServer("VICTIM", math.huge).

Math.huge is an infinite number. It will work now because

("Player or Victim", math.huge) -- math.huge is the strength.

matches

(player, strength).

The server will now accept it without errors. Hope this helps!

this is big brain talk

The player character updates into the server though, so couldnt i use that to carry over some stuff into the workspace, tho it would dissapear if my char died