Simple:
* A volcano erupting: This emphasizes the intense, uncontrolled nature of anger.
* A raging fire: This emphasizes the heat and destructive potential of anger.
* A storm brewing: This metaphor highlights the building tension and potential for chaos.
More complex:
* A tightly wound spring: This illustrates the pent-up energy and potential for sudden release.
* A poisoned chalice: This metaphor highlights the destructive nature of anger, even if it feels good in the moment.
* A caged animal: This emphasizes the feeling of being trapped and wanting to break free, often in a harmful way.
* A dark cloud hanging over you: This suggests the feeling of being weighed down and suffocated by anger.
* A river overflowing its banks: This emphasizes the feeling of being overwhelmed and out of control.
Figurative Language:
* My blood boiled.
* I felt my temper flare.
* My rage was a consuming fire.
* The anger was a heavy weight on my chest.
The best metaphor to use will depend on the specific context and the nuances of the anger you want to convey.