The captain

 

Name: Shōsei Sakaguchi
Origin: Busou Renkin
Gender: Male
Classification: Human Alchemy Warrior
Age: Unknown
Powers and Abilities: Super strength, speed, durability, endurance, Buster Baron's hands and feet can detach for independent use, able to combine with other Busou Renkin
Weaknesses: The rocket pack on Buster Baron's back only allows it to fly for short periods of time (it's normally used for charging attacks), abilities are limited by its large size, only able to use the abilities of 5 Busou Renkin at a time
Destructive Capacity: At least large building level+ via powerscaling | City level+ (especially when using the abilities of other Busou Renkin)
Range: Several hundred meters whilst in Buster Baron, otherwise average human melee range presumably
Speed: Hypersonic+ | Massively hypersonic+ movement speed (at least triple digit level, can only be maintained for a short amount of time)
Durability: Likely at least large building level+ | Likely city level+
Lifting Strength: Class 10 Class 100
Striking Strength: Class KJ+
| At least Class TJ+
Stamina: No doubt very large being a top tier
Standard Equipment: His Busou Renkin Kakugane XVII, Buster Baron, a gigantic knight-like robot 57 meters high with a weight of 550 tons, which can function as a spaceship
Intelligence: Very intelligent, is also a skilled combatant, most likely the most skilled in the entire manga
Notable Attacks/Techniques:

Buster Knuckle: Buster Baron throws a powerful punch at the enemy.

Knuckle Guard: Buster Baron thrusts toward the enemy with enough force to destroy their body.

Notable OBD Victories:

Notable OBD Losses:

Other:

Key: Shōsei Sakaguchi | Buster Baron