Here is the full list of all 67 Crystal Maidens achievements.
Upgrade 30 legendary items to the level 5
Lose 500 battles
Upgrade 10 legendary items to the level 5"
Find 10 legendary items in the Campaign Mode
Upgrade 30 epic items to the level 5
Find 5 legendary items in the Campaign Mode
Upgrade 10 epic items to the level 5
Find a legendary item in the Campaign Mode
Upgrade 1 legendary item to the level 5
Upgrade 1 epic item to the level 5
Upgrade 30 rare items to the level 5
Upgrade 10 rare items to the level 5
Upgrade a building up to level 10
Upgrade 30 common items to the level 5
Play 500 battles with Mage class
Upgrade a skill to the level 20
Earn 180 stars in Campaign 1
Play 500 battles with Marksman class
Lose 100 battles
Complete 200 quests
Upgrade 1 rare item to the level 5
Play 500 battles with Support class
Play 500 battles with Engineer class
Earn 1 million coins in Campaign Mode
Upgrade 10 common items to the level 5
Romance 15 maidens to level 3
Complete 50 quests
Get a hero up to level 60
Play 100 battles with Marksman class
Upgrade 1 common item to the level 5
Play 50 battles with Marksman class
Win 50 battles with all 3 stars
Lose 50 battles
Play 100 battles with Support class
Play 100 battles with Engineer class
Earn 250.000 coins in Campaign Mode
Play 50 battles with Engineer class
Play 100 battles with Warrior class
Own 15 maidens
Complete level 60 of Campaign Mode
Romance 5 maidens to level 3
Kill 1000 enemies in battle
Upgrade a building up to level 5
Complete 10 quests
Play 50 battles with Support class
Play 100 battles with Mage class
Get a hero up to level 30
Romance 2 maidens to level 3
Earn 120 stars in Campaign 1
Win 20 battles with all 3 stars
Own 10 maidens
Play 15 days in a row
Play 50 battles with Mage class
Kill 250 enemies in battle
Complete level 30 of Campaign Mode
Earn 60 stars in Campaign 1
Play 7 days in a row
Upgrade a skill to the level 5
Kill 100 enemies in battle
Upgrade a building up to level 2
Play 50 battles with Warrior class
Earn 5000 coins in Campaign Mode
Get a hero up to level 10
Win 5 battles with all 3 stars
Own 5 maidens
Complete level 1 of Campaign Mode