As the current head of House Veltiston, one of the four noble families that rule the superpower Aftokrator, Hairein has an immense degree of political as well as military power. Fittingly, he is in possession of a mighty Black Trigger. However, his primary role seems to be that of a commander, concocting strategies, directing his subordinates, and entering the fray only when the situation calls for it. His abilities in this regard are testified by the conquest and annexion of Galopoula as a vassal country, which was taken by an expedition led by Hairein. He masterfully orchestrated the large-scale invasion of Mikado City, with Border playing into his hands and unable to figure out his next move or his true objectives for the most part. Although his schemes were eventually thwarted thanks not in small part to Jin's precognition abilities, Hairein was able to infer the existence of someone who had pulled the strings of the whole invasion. According to Jin himself, the final outcome of the attack matched the second or third best scenario he had seen, and it still resulted in the kidnapping of several C-Rank agents, a few casualties and multiple injuries.
The scope of Hairein's competences is not limited to warfare, as he is equally capable of managing the precarious power balance of his planet-nation. He is also a clever manipulator. In combat, he can count on the crushing power of Alektor, which he is very adept at using. Having been implanted with Trion Receptors, he has a vast amount of trion of high quality that permits him to use his Black Trigger for long periods of time and with great accuracy. He can come up with tactics even to defeat opponents he is incompatible with. He demonstrated surprising agility and reflexes against Miwa, taking only a few superficial sword hits from his relentless flurry of attacks.
The horns installed on Hairein's head have improved the amount and quality of his trion over the course of years, giving him extraordinary reserves that permit him to use his Black Trigger for long periods of time. His Trion Receptors have turned black as a result of him using a Alektor.
When in his trion body, Hairein is protected by an armored cape that can deflect the bullets of Border's Gunner Triggers, as well as absorb the effects of Lead Bullet, shedding the affected parts and regenerating moments afterwards.
This Black Trigger allows Hairein to generate animal-shaped bullets from an ovoid core which hovers above his hand. Upon contact with a trion construct, they destabilize it and, if the damage is sufficient, turn it into an indestructible trion cube. Alektor thus effectively allows Hairein to neutralize opponents without them being able to defend themselves or counterattack, as their Triggers will also be cubified. Hairein is highly skilled with Alektor, choosing the type of bullet most suited to the situation and controlling their complex movements with mastery, even when multiple types are being used at the same time.