Here is the full list of all 22 Draco Knight achievements.
Collect 5 manna
Earn 10 skills
Defeated the orc hunter and his partner
Defeat the slavers
Collect 5 ambrosia
Earn 3 skills
Defeat a great mounted foe
Saved the scout from a grim fate
Earn a new skill
Defeated your first great foe.
Take your first taste of manna
Take your first taste of ambrosia
Defeated the reaper
Defeated the mounted wyvern rider
Defeated the orc knight
Spared the wolf
Gathered a group of unlikely allies
Earn all achievements
Completed the Game
Earn all skills
Collect 10 ambrosia
Collect 10 manna