Here is the full list of all 40 Dark Flame achievements.
End Level - 30
End Level - 29
End Level - 28
End Level - 27
End Level - 26
End Level - 25
End Level - 24
End Level - 23
End Level - 22
End Level - 21
End Level - 20
End Level - 19
End Level - 18
End Level - 17
End Level - 16
End Level - 15
End Level - 14
End Level - 13
End Level - 12
End Level - 11
End Level - 10
End Level - 9
End Level - 8
End Level - 7
End Level - 6
End Level - 5
End Level - 4
End Level - 3
End Level - 2
End Level - 1