Alex borrowed a friend’s old MacBook Pro from 2012. They used it to download a trusted copy of the Lion installer from a known vintage software archive (like archive.org, where some users have uploaded verified copies of the original Apple installer files). Then, using a 8GB USB drive and the createinstallmedia command in Terminal, Alex made a bootable Lion installer. No shady ISO required.
: Running Mac OS X Lion within software like VMware or VirtualBox for testing. macos x lion iso
The safest way to get the installer is directly from Apple. While they don't provide a "ready-to-go" ISO, they do provide the .dmg installer. Alex borrowed a friend’s old MacBook Pro from 2012