Seikon no Qwaser/Awesome

• During Chapter 10 of the manga, Yuu (oxygen) has Sasha on the ropes during their fight at the school. He's slowly increased the concentration of oxygen in the air in the room to the point that any time Sasha's iron weapons strike a spark, it flares up dangerously. The high O₂ levels are also making it difficult for Sasha to breathe. Outside the room, however, Mafuyu realizes what's going on. She puts cardboard boxes up against the door and sets them on fire, and then throws her kendo stick through the window set in the door. The super-oxygenated air causes the fire to expand into the room, rather vigorously. not bad for someone without any Elemental Powers.