Here is the full list of all 40 Glitchangels achievements.
Defeat the archangel Ariel
Defeat the archangel Raphael
Defeat the archangel Azrael
Defeat the archangel Jophiel
Defeat the archangel Michael
Kill all enemies on level 9
Kill all enemies on level 17
Kill all enemies on level 24
Kill all enemies on level 36
Kill all enemies on level 42
Destroy Boss Qemuel
Destroy Boss Belphegor
Destory Boss Asmodeus
Destory Boss Xaphan
Destroy Boss Castiel
Complete Assault 5 without getting hit
Complete Assault 15 without getting hit
Complete Assault 25 without getting hit
Complete Assault 35 without getting hit
Complete Assault 45 without getting hit
Collect a lifetime total of 500 skulls
Collect a lifetime total of 1,000 skulls
Collect a lifetime total of 2,500 skulls
Collect a lifetime total of 5,000 skulls
Collect a lifetime total of 10,000 skulls
Destroy a lifetime total of 10 boss turrets
Destroy a lifetime total of 25 boss turrets
Destroy a lifetime total of 50 boss turrets
Destroy a lifetime total of 100 boss turrets
Destroy a lifetime total of 250 boss turrets
Collect a lifetime total of $50,000
Collect a lifetime total of $100,000
Collect a lifetime total of $150,000
Collect a lifetime total of $200,000
Collect a lifetime total of $250,000
Score a total of 100,000 in a single game
Score a total of 200,000 in a single game
Score a total of 300,000 in a single game
Score a total of 400,000 in a single game
Score a total of 500,000 in a single game