Hydreigon's Weaknesses

Best Counters

Hydreigon is especially weak against Fairy type Pokemon, they will deal 4x damage to it!

The types that are strong against Hydreigon are Fairy, Bug, Fighting, Ice type Pokemon.

For the best defense, Fairy types have very effective defense against Hydreigon, and will be resistant to damage from Hydreigon's STAB attacks:

Dragon types will also deal super-effective damage against Hydreigon, but be careful using Pokemon of this type because they may also receive extra damage from some of Hydreigon's attacks!

Weaknesses

Hydreigon's type is Dark and Dragon.

Hydreigon is especially vulnerable to Fairy attacks, it will receive a super effective four times (4x) the amount of damage! Since Fairy type Pokemon are especially strong against Hydreigon, you should attack with this type of Pokemon.

Hydreigon has a weakness to Fairy, Bug, Dragon, Fighting, Ice types. These Pokemon types will be strong against Hydreigon, causing Hydreigon to take a super effective quadruple (4x) damage from Fairy type attacks, and causing Hydreigon to take a super effective double (2x) damage from Bug, Dragon, Fighting, Ice type attacks.

Psychic type attacks will have no effect on Hydreigon, as Hydreigon is immune to this type of damage! Please avoid these types of attacks.

Please keep in mind that Hydreigon is resistant to attacks from Dark, Electric, Fire, Ghost, Grass, Water types, and these attacks are not very effective and cause reduced damage, so they should be avoided.