It sounds like you're referring to a custom firmware (CFW) or a bypass method for the iPhone 5 on iOS 10.2, possibly related to iCloud unlock, with "animetrick.com" as a source.
Animetrick and similar platforms provide modified files and instructions for legacy devices. For the iPhone 5 on iOS 10.2 or 10.3.4, the process typically follows these steps:
But there was a catch. This "bypass" was often tethered or lacked cellular signal. Like many who followed the animetrick.com rumors, Leo found himself with a powerful iPod touch rather than a working phone. While tools like Sliver and 3uTools eventually made these processes more reliable, the original animetrick era remained a wild, experimental chapter in iPhone history.
Firmware Management: 3uTools is used on Windows to "Quick Flash" the device with compatible iOS 10.x firmware.
For older 32-bit devices like the iPhone 5, users often rely on local tools rather than web-based services: Sliver (by AppleTech752)