I hear you!
"Please make multiplayer achievements available in solo."
It takes time to understand this wish, but there you go, who am I to judge right? You want to complete the hardest Multiplayer achievement in the game in SOLO, I got you!
Junkyard is added. Go to
Multiplayer->Lobbies->Create->Junkyard
And kill those little ships!
"Top1 is now Top GUN!"
Okay, you don't have to grab the first place in the leaderboard. Top5 is good from now on.
Cheers,
OldMan