Don’t know exactly what it could do, but it is definitely a virus. Delete that, and it also makes no sense, as a welding script would not secure your game from exploiters. And as @ram4c said,
Delete it and just go on with life, good luck on whatever you are building!
It’s a backdoor, I decoded it down and it took me to this module:
This is the layout of a backdoor I could dump the constants of the obfuscated script inside but i’m to lazy if you want to do that yourself then here’s a tutorial:
You are wrong, this is not a lag nor a promptpurchase script. The script can be easily reverse-engineered using require=print! This is a ROBLOX backdoor which users sell access to buyers. This basically allows people to exploit your game and bypass filtering enabled as this is server-sided.
Why would you need to reverse engineer it with require=print? The equation is simple math it will take a simple google search to trace it back to the module.