Ninjask's Weaknesses

Best Counters

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

The types that are strong against Ninjask are Rock, Electric, Fire, Flying, Ice type Pokemon.

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

Weaknesses

Ninjask's type is Bug and Flying.

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

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

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

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