As their attacks seemed to be having no affect whatsoever, and didn't even illuminate a weak point, Silef let them fade. She had no idea how they would get through that armor, but she was contributing nothing standing here. That and Dust's commentary irked her. She started to gather energy internally when Dust began to advance towards her, the earth rippling at his tread. She dodged sideways with an acrobatic roll, jumping through the air and coming deftly to her feet once she ran out of momentum.
Silef began shouting as she planted her feet, bracing herself for what she was about to do. "You may be the mighty Lord of Heroes out of legend, but do not doubt the power coursing through my veins! I am a true heir of Asterlux, and our power has been said to rival the very heavens!" It wasn't said that way, of course, but Silef's intention was not simply to boast. Shouting moved breath and energy though the body, and helped the sorceress focus. The power that was building in her, the power she spoke of, showed very clearly as the noblewoman began to literally glow slightly. Her eyes became a golden color as she channeled the power, and her palms - which were both faced toward Dust now - were almost impossible to look at as the energy gathered in front of them.
A short moment after Silef finished her yelling, she released the attack, which took the form of a bar of blazing, golden light that lanced toward Dust. She aimed for his chest; ideally the attack would travel too quickly for him to dodge, but she wasn't familiar with all of her opponent's abilities.