"If no other options are available, or if the opportunity presents itself." Weird question. There are decorative elements on the Kimaris, but the horn can (and has been) useful. "The horn is barely a weapon, considering the arsenal it's equipped with, though."

As for Duo's other question... "Well, the frames haven't been made since the Calamity War. Because of the dual Ahab Reactors, the technology required is immense. Nanolaminate made from Mars' halfmetal is the standard for the armor."

{{ ooc: aka, literally nothing exists online that I can find that actually mentions what the frames were made of. Gaelio would probably know the actual answer, given we see people looking at tech specs for the frames in the series, but 🤷 }}