Mailed fists are a powerful image of strength and aggression, but there are many other ways to describe this idea. An alternative might be "clenched fists," which conveys tension and anger without quite the same level of readiness for combat. Similarly, "balled fists" could be used to suggest frustration or a need for control. A more poetic take might be "knuckled hands," which emphasizes the physicality of the gesture. In a more confrontational context, "raised fists" or "combatants' fists" could be appropriate. Ultimately, there are many ways to describe the image of fists held tight in preparation for battle, and each conveys a slightly different shade of meaning.