Here is the full list of all 58 The Last One Month achievements.
Completed 1 game
Completed 10 games
Completed 50 games
Completed 100 games
Completed 200 games
Completed 500 games
Achieved 1st place in the game once
Achieved 1st place in the game 50 times
Achieved 1st place in the game 100 times
Achieved 1st place in the game as Chivalrous Warden
Achieved 1st place in the game as Holy Paladin
Achieved 1st place in the game as Spanning Spitfire
Achieved 1st place in the game as Steam Gunman
Achieved 1st place in the game as Demonic Hierarchist
Achieved 1st place in the game as Abyss Inquisitor
Achieved 1st place in the game as Celestial Seer
Achieved 11th place in the game 11 times
Achieved 10th place in the game without any battles
Achieved a total of 100 battles
Achieved a total of 300 battles
Achieved eliminate more than 1 user in one game
Achieved eliminate more than 4 users in one game
Achieved recruit Allies and NPC 10 times
Achieved recruit Allies and NPC 100 times
Achieved recruit Allies and NPC 300 times
Achieved intrusion 10 times
Achieved intrusion 50 times
Achieved intrusion 100 times
Achieved bribe recruitment 10 times
Achieved bribe recruitment 50 times
Changing to a different Class 1 time (Including Class Changes)
Changing to a different Class 10 times (Including Class Changes)
Used Reincarnation Sanctuary 10 times
Used Well 10 times
Used Banner 10 times
Used Stable 10 times
Used Taiming 10 times
Used Inn 10 times
Used training center 10 times
Achieved Dungeon Clearing 10 times
Achieved 10 times of opening up the treasure chest
Achieved maximum aggressive alignment
Achieved maximum friendly alignment
Achieved 50 battles against the dark army
Acquired 16 level legendary grade weapon
Acquired 16 level common grade weapon
Achieved mythic grade npc 16 level
Achieved beginner grade npc 16 level
Achieved 1st place as Void Wizard
Achieved total 10 battles
Achieved total 500 battles
Achieved eliminate more than 10 users in one game
Level 2 Achieved!
Level 3 Achieved!
Level 4 Achieved!
Level 5 Achieved!
Level 6 Achieved!
Level 7 Achieved!