From Dragon Quest Wiki

Anti-dragon is a skill introduced in Dragon Quest Monsters: Joker.

Dragon Quest Monsters: Joker[edit]

Anti-dragon is naturally learned by the Boss troll and Restless armour. It grants the following abilities:

Ability Skill Points
Dragon Slash 5
Insulate 10
Blowback 18
Gobstopper 28
Breathtaking Bash 38
Insulatle 50
Brake Wind 64
Fire Breath Guard 80
Cold Breath Guard 100

Dragon Quest Monsters: Joker 2[edit]

Anti-dragon is also learned by the Hyper heyedra. Its abilities remain unchanged.