Originally Posted by SteaL K1LL
Need to trade with 6 more people online
send me a Message even when I'm playing other games ill jump out and trade with you guys my Gamertag is: SteaL K1LL
Host a game of co-op and a random person will join. Fire up the game, head over to the shop and trade something with them. Do this 6 more times and your achievement will unlock.