Calyrex's Weaknesses

Best Counters

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

The types that are strong against Calyrex are Bug, Dark, Fire, Flying, Ghost, Ice type Pokemon.

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

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

Weaknesses

Calyrex's type is Psychic and Grass.

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

Calyrex has a weakness to Bug, Dark, Fire, Flying, Ghost, Ice, Poison types. These Pokemon types will be strong against Calyrex, causing Calyrex to take a super effective quadruple (4x) damage from Bug type attacks, and causing Calyrex to take a super effective double (2x) damage from Dark, Fire, Flying, Ghost, Ice, Poison type attacks.

Please keep in mind that Calyrex is resistant to attacks from Electric, Fighting, Grass, Ground, Psychic, Water types, and these attacks are not very effective and cause reduced damage, so they should be avoided.