Here is the full list of all 31 League of Maidens achievements.
REACH AWAKENING LEVEL 1
REACH AWAKENING LEVEL 5
REACH AWAKENING LEVEL 10
REACH AWAKENING LEVEL 15
REACH GUARDIAN LEVEL 5
REACH GUARDIAN LEVEL 10
REACH GUARDIAN LEVEL 15
MAX LEVEL ALL SKILLS, PERKS & ABILITIES
GET 7 DAY DAILY CHALLENGE STREAK
Enter the 15th Gate
KILL 1,000 SOLDIERS
DESTROY 500 TANKS
Defeat the final boss "The Union" on ULTRA HARDCORE mode.
Defeat the final boss "The Union" without using self heal, potions etc.
Defeat the final boss "The Union" without taking any damage.
KILL 1,000 FILTH
KILL 1,000 REMAINS
KILL 1,000 SWARM
KILL 1,000 BOMBER
KILL 1,000 FOUL
KILL 1,000 NIGHTMARE
KILL 1,000 BRUTE
KILL 1,000 CREEPER
KILL 1,000 FIEND
KILL 1,000 SCAVENGER
KILL 100 ELEMENTAL
AWAKEN AND PRESTIGE 1 WARMAIDEN
KILL 1000 ENEMIES WITH A SNIPER RIFLE
MAKE ANY PREMIUM SHOP PURCHASE
COMPLETE ALL 29 ACHIEVEMENTS
EARN 10 MILLION XP WHILE PLAYING ON ULT. HARDCORE MODE.