First id go look up the word powerful in a thesaurus and find some synonyms to help me with the interpretation.
Then i would use these definitions to go a bit off base with it.
Powerful Synonyms, Powerful Antonyms | Thesaurus.com
able, all-powerful, almighty, authoritarian, authoritative, capable, cogent, commanding, compelling, competent, controlling, convincing, dominant, dynamic, effectual, efficacious, energetic, forceful, forcible, impressive, in control, in the saddle, influential, mighty, omnipotent, overruling, paramount, persuasive, potent, preeminent, prevailing, puissant, robust, ruling, sovereign, stalwart, strapping, strengthy, sturdy, supreme, telling, upper hand, vigorous, weighty, wicked*, wieldy
With the antonyms: impotent, incapable, ineffective, unable, weak
So id work with one or two of those words and see what i could come up with.