A person or force that causes havoc or widespread destruction.
Agent noun formed from 'havoc' plus the '-er' suffix, creating 'havocker' to mean 'one who causes havoc.' The suffix '-er' transforms verbs into nouns describing the agent performing the action.
While 'havocker' isn't commonly used today, it's a perfect example of how English's '-er' suffix is incredibly productive—you can add it to almost any verb to make an agent noun, and most people will understand it immediately.
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