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