Games on Roblox have their own currency, skins, weapons, vehicles, accessories, and much more. All these items can be bought in-game as well as through redeem codes.

For example, you can import a sports car into Roblox Studio without spending a cent. For more Roblox tips, check out Roblox's own walkthroughs and my books on how to script games.

Knives are a weapon for killers in-game, and there are plenty of them in Roblox Murder Mystery 2. These knives are ranked via a tier list.