Here is the full list of all 48 Remaya Idle achievements.
Rebirth 50 times.
Acquire 1000 Legendary Items.
Rebirth 30 times.
Reach Level 500
Reach Level 400
Use 500 Books.
Reach Knowledge Level 100.
Enter 100 Dungeons.
Reach Level 300
Reach Knowledge Level 75.
Rebirth 15 times.
Reach Knowledge Level 50.
Reach Level 200
Reach Knowledge Level 30.
Enter 25 Dungeons.
Gain 500 Equipment.
Reach Knowledge Level 15.
Acquire 100 Legendary Items.
Rebirth 7 times.
Enter 10 Dungeons.
Destroy 10000 Targets.
Use 100 Books.
Rebirth 3 times.
Reach Knowledge Level 5.
Use 1000 Potions.
Destroy 5000 Targets.
Enter a Dungeon.
Gain 100 Equipment.
Rebirth 1 time.
Use 500 Potions.
Destroy 2000 Targets.
Acquire 10 Legendary Items.
Use 25 Books.
Reach Level 100
Destroy 1000 Targets.
Reach Level 75
Destroy 500 Targets.
Gain 25 Equipment.
Use 100 Potions.
Acquire a Legendary Item.
Reach Level 50
Use a Book.
Reach Level 20
Destroy 100 Targets.
Use 25 Potions.
Gain an Equipment.
Reach Level 5
Use a Potion.