Here is the full list of all 50 Apocalypse Knights 20 - there are The Angel Awakens achievements.
Own 5 rides
Kill 100 Raptor demons
Level 1 difficult all pass
Own Nightmare Set
Own Crusader Set
Kill 1000 demons with Spear
Kill 100 FaceCube demons
Save 100000 coins
Character level reaches 30
Own 5 Spears
Own 5 Broadswords
100 combos
Kill 1000 demons with Broadsword
Kill 1000 demons
Kill 100 demons with Ultimate Skill
Pass 20 Waves in a row
Kill 500 demons
Character level reaches 10
Own Alloy Set
Own Steel Set
Kill 100 demons
Own 5 Lances
Kill 1000 demons with Lance
Own Centurion Set
Own Templar Set
Own Bloodlust Set
Own Imperial Set
Own Demon God Set
Own Ghost Set
Own 5 armors
Character level reaches 50
Character level reaches 100
Get 30 perfect wave
Get 100 perfect wave
Level 2 difficult all pass
Level 3 difficult all pass
Level 4 difficult all pass
Level 5 difficult all pass
Level 6 difficult all pass
Level 7 difficult all pass
Level 8 difficult all pass
Level 9 difficult all pass
Level 10 difficult all pass
Pass 40 Waves in a row
Pass 60 Waves in a row
Kill 1000 demons on a horse
Kill 10000 demons
Kill Fire Devil
Kill 10000 FaceCube demons
Kill 10000 Raptor demons