Nothing happened for five seconds. Then, his inventory began to glitch. The single "Golden Barbell" he owned started multiplying. One became ten. Ten became a hundred. His strength stats began to roll over like a broken odometer—millions, billions, quadrillions.
Simple macro recorders that simulate mouse clicks. These are harder to detect because they don't inject code into the Roblox client.
Scripts that bypassed the server-side checks to inflate strength stats (though these often resulted in a "kick" from the game).