Mainframe is a giant computer program that simulates the real world, and it was built by the PL80 organization.

Sites in Mainframe are connected by API Routes and you can hack into the Backend to travel between them. Some Sites have high security, so you'll have to improve your hacking skills to access them.

Your first time traveling through an API Route will be challenging because they are littered with Bots and NikNaks that you need to battle.

But once you've hacked into a Site, you can create a Backdoor which allows you to take a shortcut directly to it, bypassing the API Route entirely.

As you progress in the Mainframe, your hacking skills will increase as the NikNaks that you command become more powerful and you collect more resources.