Strongarms are Silvers who possess superhuman strength. Their bodies are enhanced in durability to crush, lift, throw, and catch objects of immense weight. The stronger ones can make shockwaves by clapping and mini earthquakes in small areas by stepping hard. The things they throw burn air by how strong they throw them. They can also jump very high.
"Strongarms are perceptors with enhanced strength and durability well beyond the normal range of human capability. Strongarms are brawlers beyond nature, best suited to the arenas of Norta or border patrol between hostile nations." - On Silverblooded Abilities by Victoria Aveyard