Endless Sky

Endless Sky (장천, Jangcheon, "Long Pierce") is a technique that concentrate Shinsu between hands and fired it as powerful beam blast with ripples spreading around it towards the target.

About
This seems to be one of Yu Han Sung's original technique. Baam seems to copied this technique during his training with Yu Han Sung in FUG after the Part I.

Twenty-Fifth Baam
Baam Style - Shinsu Control Skill: Endless Sky (밤류 신수제어술 장천, Bam-lyu Sinsujeeosul Jangcheon) is a technique used by Baam, while using his own shinsu control. At first Baam concentrated black shinsu between his palms before he fired it as black shinsu beam at his opponent. It is presumed that Baam learned this technique first from Yu Han Sung, and then used it with his Orb and later with his own shinsu.

Twenty-Fifth Baam also used this technique in the Last Station by transferring it into the Black March to multiply it's power.

Yu Han Sung
Yu Han Sung Style - Shinsu Control Skill:  (유한성류 신수제어술 장천, Yoo Hahnseong-lyu Sinsujeeosul Jangcheon) is Yu Han Sung's own shinsu technique. After concentrating shinsu between his hands, he fired it as powerful beam with ripples spreading around it towards his target.

Trivia

 * It seems to be a derivation or variation Orb - Endless Sky, albeit without the orb as a means to enhance shinsu.
 * This technique might be derived from Straight-Line Long Pierce or it might be some version of it. It shares Hangul characters: 장천.