Ascendent Archery
During that night, Sigma was stuck on guard duty without moving an inch while staring at nothing. Only thinking about how he could improve his own technique. Getting better with the bow seemed like it was only a matter of raising one's accuracy. However, that wasn't enough when the enemies were demons that could survive with two arrows on their heads.
In the end, the answer that Sigma fought was to keep increasing the piercing power of his arrows, just like the wind arrows could pierce a bit more. Still, instead of using them, Sigma practiced using the ice arrows… for several hours, shooting at nothing and just making his arrows fly in the darkness for hundreds of meters until he finally came up with something… making the arrows spin as they flew toward the enemies.