From Pluralpedia, the collaborative plurality dictionary
intimidator (n.)
Applies toheadmates

An intimidator is a headmate who uses intimidation tactics to protect others in the system.

This often takes the form of scaring off an attacker before an attack can occur.

Intimidators are a subset of protectors, although they can also be considered a subset of gatekeepers. As such, the term intimidator functions as a system role.