dont think there's a full list of either missions or achievements but pretty sure they've changed from when i started 2-3 years ago; for a current list of achievements either creating a new login or going through all the game updates from when they added frontier dungeons and awakened toons would be the other way as thats when they overhauled the achievements tab and kept adding more with each dungeon and awakened toon. also cant remember last time any mission challenge worked for me.