All Tiers
Knockers are quick, diminutive, Gremlins that wear colored goggles and wield two Wrench Wands. The color of these match the minerals used to make the theme status - for example, a Jumper's goggles and wrench color are blue and purple, matching the minerals that create shock themed levels. Knockers attack by slamming their wands near a knight and causing an explosion, which can inflict a status condition and even knock enemies around. These explosions occasionally backfire, creating a larger explosion that can potentially inflict stun on those (including the Gremlin Knocker) caught in the explosion. Knockers do not appear to belong to any clans, so they do not behave differently further down in the Clockworks.
No Knocker is immune to its own dealt status effect.
To determine if the attack misfires, Knockers will emit a sound similar to a Darkfang Thwacker executing a spin attack, and the attack tends to be executed considerably slower.
After tier 1, Knockers deal elemental damage if their attacks connect.