Here is the full list of all 12 Bengan Yes achievements.
Played Bengan Yes
Have 10 characters in your game!
Have 100 characters in your game!
Have 1000 characters in your game!
Have the hackerman ReeZey join your game
Have the CREATOR Addemannen1 join your lobby
Have the insane 3d artist 123meinkratf join your lobby
Win in your own lobby... Shameful
Have the REAL LucasNagy join your lobby
Have the MONKE August join your lobby, smile
Have the max amount of players joined to your round (20640)
Finish the Bengan Bros campaign