A hint for the big fight before you get the achievement:
I failed some times in the fight on hard difficulty, because there were too much enemies (especially the fire-man and the handyman in combination with the guys on the ship).
Try to kill some "regular enemies" until the handyman spawns.
Then go up to the sky-line and "drive" a round. Jump off to the highest platform (try to sky-attack an enemy), wait 2 seconds and jump back again to the sky-line (but not in the opposite direction).
This is necessary so the handyman does not charge up the sky-line to damage you.
"Drive" these rounds some times and the handyman jumps off the level and dies. If this is happen, kill the remaining regular enemies and meet Elisabeth in the middle of the plattform.
I tried this method 5 times, to ensure that it was no luck and it worked every 5 times. The average of "driven rounds" until the handyman jumps off the level was 5 rounds.
I hope it helps you, too, if you are stuck on this fight.