Always create a copy of your existing save files before replacing them. Disable Cloud Sync: If using Steam, disable Steam Cloud sync
You're looking for information on a Prototype 2 save game with a specific skin, namely the Alex Mercer skin. prototype 2 100 save game with alex mercer skin
Console users can use USB drive save editors or modded consoles, but this is more complex and carries online ban risks—so most console players grind the unlock legitimately. Always create a copy of your existing save