Here is the full list of all 21 Vengeful Castle achievements.
Slain 10 enemies
Slain 100 enemies
Slain 1000 enemies
Slain 10000 enemies
Slain 100000 enemies
Slain 1000000 enemies
Slain 10 bosses
Slain 100 bosses
Slain 1000 bosses
Dodge 1000 times
Clear difficulty 10
Earn 10000 golds from enemy
Earn 100000 golds from enemy
Earn 30 stacks of twin dice
Earn 1000 potions from enemy
Hit 15 enemies with thunder clap flash
Full charge attack 30 times
Restoring 1000 HP with diversion
Earn 100 bonus SWORD DAMAGE with Courage
Any difficulty level Castle Crawl stage cleared
Clear difficulty 4