General:
* Activity
* Deed
* Doing
* Execution
* Movement
* Performance
* Process
* Response
* Work
Intensity:
* Bold
* Energetic
* Forceful
* Powerful
* Vigorous
* Zealous
Purpose:
* Deliberate
* Intentional
* Purposeful
* Strategic
* Tactical
Nature:
* Aggressive
* Courageous
* Defensive
* Offensive
* Proactive
* Reactive
Outcome:
* Effective
* Fruitful
* Productive
* Successful
* Valuable
Other:
* Bold
* Courageous
* Dramatic
* Heroic
* Immediate
* Instantaneous
* Spontaneous
* Urgent
Figurative:
* Catalyst
* Driving force
* Engine
* Fuel
* Spark
* Trigger
Negative:
* Reckless
* Rash
* Hasty
* Impulsive
* Desperate
* Aggressive (in a harmful way)
The best word to describe action depends on the specific context. Consider the type of action, its intensity, purpose, and outcome when choosing a word.