yeah the same game twice. generally a remaster or goty/special edition/etc.

It went something like: friend: hey grass I got you a game! me: oh cool thanks. *redeems game without thinking... me: wait I already have this friend: its the special edition. me: but I'll have to get the achievements a second time. friend: you won't do that, your only all achievement game is mw2.

then other friends got me more duplicates because they knew I would be an idiot and do it repeatedly to 'prove a point'. In the end a miserable time. The easiest were the souls games because once you learn the controls they are all the same, apart from the different enemy placements in ds2. hardest was probably between the older version of kingdom or old bioshock 2 due to buggy achievements and the ungodly amount of time doing the exact same thing until it worked