Some stuff that came across my mind would be:
- Creating a certain number of collection folders and filling those up with a certain amount of maps. (Organized)
- Hitting F2/clicking random a certain amount of times (???)
- Beat your score x times in a row (You've Got To Believe!)
- Be the last one standing and able to finish without dieing in a team battle with over x players in your team without no fail/relax/auto pilot mod (possibly even an achievement for still winning afterwards?) (The Lone Wolf)
- Bring the HP bar back to max from X % in Co-op Tag X of times during a map. Again without the no fail/relax/auto pilot mod. (Life Saver)
Didn't go back to check all pages, so my apologies if there's some dupes in there.
- Creating a certain number of collection folders and filling those up with a certain amount of maps. (Organized)
- Hitting F2/clicking random a certain amount of times (???)
- Beat your score x times in a row (You've Got To Believe!)
- Be the last one standing and able to finish without dieing in a team battle with over x players in your team without no fail/relax/auto pilot mod (possibly even an achievement for still winning afterwards?) (The Lone Wolf)
- Bring the HP bar back to max from X % in Co-op Tag X of times during a map. Again without the no fail/relax/auto pilot mod. (Life Saver)
Didn't go back to check all pages, so my apologies if there's some dupes in there.