on the warpath

1.
WorldwideUSUKinformalcolloquial
- Angry and ready to confront, punish, or demand redress; in a state of hostile agitation.
- Acting in a determined, aggressive manner toward a person or group because of perceived wrongs.
2.
WorldwideUSUKinformalfigurative
- Actively campaigning, mobilizing, or mounting an offensive (verbal or political) against a target or cause.
- Persistently pursuing complaints or investigations with the intention of challenging or defeating an opponent.

Examples: