To unlock this achievement you simply need to revive a fallen teammate that is bleeding out after being shot in ranked matches. Since no one is playing the online anymore, the fastest way to get this done is with a couple of boosting buddies. One buddy on the opposing team to shoot your other buddy on your team. When they drop to the ground you hit the " Y " button to revive him. Repeat this action until the match ends and depending how quick you are with the revives you can get over 100 revives per match. At that rate this achievement should unlock in about five matches.