ATX team leader Assault 1 is a second lieutenant (少尉) named Kyosuke. He pilots the PTX-003C Alteisen, also known as Alteisen Riese in its upgraded version PTX-003C-SP1. Kyosuke is recognized for his exceptional combat skills and strategic thinking on the battlefield. Despite being reserved most of the time, he has an incredible ability to predict enemy behavior accurately.
Kyosuke's luck seems unbelievable as he often survives terrible accidents and dangerous battles without harm. He enjoys gambling and consistently bets on the least favorable side. Kyosuke forms a formidable team with Excellen, both in their PTs and privately as they are a couple. Although he appears to ignore her public displays of affection, Kyosuke cherishes his girlfriend more than anything else, and anyone who harms her will face the full force of his wrath.
Kyosuke holds great respect for his former commander Zanger despite his betrayal. He admires Zanger's reasoning and shares a similar personality, which is mostly stoic but with a "do-or-die" mentality in battle. With Zanger gone, Kyosuke becomes a mentor to Bullet, helping him control his impulsive behavior at times.
Later on, Kyosuke is promoted to the rank of first lieutenant and continues to lead the ATX team after Zanger decides not to return to his former unit. Alteisen suffers severe damage during this time, but Kyosuke remains dedicated to piloting it and leading his team effectively.