Killer Instinct

All the "friendly" achievements are currently bugged in a good way; you need only finish an exhibition match vs. anyone. Win or Lose, the achievement will unlock at the end of the match, unless your opponent disconnects. It doesn't matter who hosts the match.

So jump into exhibition matches, pick Glacius, finish the match, and then pick "select character" so you can get another friendly achievement. No friends or skills required.

Very easy to do. Start up a party and invite your friend to play some Killer Instinct! Go into the game and Host a exhibition match and it will automatically add your friend to the game. Both of you pick Glacius and take turns kicking each other's behinds. Let each other get a supreme victory (it should be perfect since you didn't fight back) and you'll pop this as well: