it only works for games they have in stock;
example scenario:
I trade in 4 games (10$ each tiv)
I ask for NHL 08
They do not have NHL 08
I ask for Orange Box
they do not have orange box
I ask for ________ (insert title name here) _______
they do not have _______ (insert title name here) ______
repeat until they have a game in stock you would like. I forgot to ask when it goes till, but i would expect it ending soon, perhaps for DMC4 Turok they will have a trade 4 (for those specific titles).
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JOSH NASSO PRO-TIP!!!
Once i purchased SVR2008 with this trade 4 get any, it had a weird noise in the box, sounding like the disc was broken, I gave it back with the recipt and they gave me the full amount of the game, instead of the trades. This could be YMMV, but please, dear gaming gods please, do not abuse this. If you want, say devil may cry 4, purchase a game they have, Kane and Lynch or something, do not open it and return it for store credit and buy when it comes out, but please do not rinse and repeat, they will catch on.
you're welcome.