Here is the full list of all 53 Beautiful Mystic Survivors achievements.
Defeat 400,000 enemies
Defeat 200,000 enemies
Beat level 3 with Minos
Kill 5000 enemies with Minos' active ability
Defeat level 2 final boss 3 times
Defeat a final boss with Isaya
Survive 16 minutes with Isaya
Defeat level 2 final boss 2 times
Defeat 100,000 enemies
Defeat a final boss with Ciara
Survive 16 minutes with Ciara
Win 5 times
Defeat a final boss with Rosaline
Win the first level with 3 different characters
Complete 6 secret shrine or cursed shrine challenges
Survive 16 minutes with Rosaline
Rescue Minos
Evolve Shield 3 times
Walk 10,000 meters with the Fire Boots
Defeat a final boss with Cassandra
Level up the Holy Pedant to level 4
Complete 3 secret shrine or cursed shrine challenges
Survive 16 minutes with Cassandra
Defeat level 2 final boss
Rescue Ciara
Defeat the first boss of level 2
Craft 200 potions with Sophia
Use special abilities 250 times
Defeat level 1 final boss
Rescue Melisandre
Complete secret shrine or cursed shrine challenge
Use special abilities 100 times
Evolve the Sword
Defeat 20 elite enemies with the Scythe
Pickup 100 items from the ground
Collect 5,000 gold in total
Pickup 30 healing potions
Obtain 3 legendary weapons
Defeat the first boss of level 1 3 times
Reach level 60
Pickup 50 items from the ground
Collect 1,000 gold during a single run
Collect 4,000 gold during a single run
Collect 2,000 gold during a single run
Use special abilities 50 times
Pickup 10 items from the ground
Pickup 10 healing potions
Equip 6 passive items in a single run
Obtain a legendary weapon
Defeat the first boss of level 1
Evolve the Bow
Survive 5 minutes with any character
Equip 6 weapons in a single run