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