Asteroid Users
Reiji Kizaki
Kizaki Asteroid Minigun
Kizaki has two firearms loaded with Asteroid bullets: an assault rifle and a minigun. The latter seems to be rather heavy, forcing him to hold it with both hands, and impossible to aim accurately with, but it more than compensates for it with its extremely high rate of fire. Kizaki uses it for prolonged attacks without moving from his position, deploying a Shield if the enemy returns fire. He can then switch to the assault rifle to increase his mobility.

Kyōsuke Karasuma
Karasuma Asteroid anime
Asteroid is one of Karasuma's most used offensive Triggers. His assault rifle grants him a high rate of fire. He often employs it in conjunction with Defense Triggers, such as Shield or Escudo, to protect himself while shooting.

Kōhei Izumi
Izumi Asteroid2
Izumi usually fights using Asteroid in Full Attack. Thanks to his massive amount of trion, Izumi can afford to choose hit probability through sheer numbers over accuracy, splitting his trion cubes several times. His firepower remains such that Ai Kitora was convinced her Shield would not be able to resist one of his barrages. As a masterful Shooter, Izumi is able to scatter the bullets to increase his area of attack.

Takeru Yuiga
Yuiga Asteroid
Yuiga fights primarily by dual-wielding handguns and shooting Asteroid. Although he is noted to be weaker than some B-Rank agents, he still scored more victories than losses against Osamu. According to Border's evaluation system, he has the highest range of any handgun user.

Ryō Utagawa
Ryūji Saeki
Kazuma Satomi
Jun Arashiyama
Arashiyama Tokieda Asteroid
Arashiyama fires Asteroid bullets through his assault rifle, which has a high rate of fire. He often coordinates with his teammates to increase their overall firepower or attack the opponent from multiple directions, a tactic that is rendered even more effective by the use of Teleporter. He and Tokieda were able to destroy the durable armor of an injured Rabbit in a matter of seconds.

Ai Kitora
Kitora Asteroid
Kitora fires this Trigger through her hangun, which seems to be her preferred method of attack. By fighting at a distance, she can analyze the opponent and look for openings. She can switch to an Attacker Trigger at close range, which also reduces trion consumption.

Mitsuru Tokieda
Arashiyama Tokieda Asteroid
Although his role is primarily that of a supporter, Tokieda is a capable Gunner. His weapon of choice is an assault rifle loaded with Asteroid bullets. He is always seen using it while coordinating with Arashiyama, either in a pincer attack or a frontal assault. With their combined bullet power and high rate of fire, they destroyed the durable armor of an injured Rabbit in a matter of seconds.

Nozomi Kako
Shūji Miwa
Miwa Asteroid
Miwa's most used offensive Trigger is the Asteroid. Firing it through his handgun, he can fight both at mid and close range, as this type of weapon can be used with just one hand. He often combines Asteroid with Lead Bullet. He seems to be a very skilled Gunner, matching Arahiyama and Tokieda in a gun fight with Izumi's assistance.

Takaaki Katagiri
Masataka Ninomiya
Ninomiya asteroid anime
As the Shooter with the highest score with this Trigger,[1] and the agent with the second highest score with any Trigger, Ninomiya is extremely proficient with Asteroid. Thanks to his abundance of trion, a single volley is powerful enough to break the Shield of a former A-Rank agent and damage their body,[2] as well as to destroy small structures.[3] He scatters his bullets evenly around him, targeting an area that is larger than the opponent, but not so much that too many shots will miss the target.[2][4] Ninomiya is capable of create trion cubes with his hands in his pockets[5] as well as to summon, divide and fire one before the opponent can react.[6] Due to Ninomiya dividing the trion cube in 6[5] or 16[2] parts, his bullets are shaped like pyramids.

Sumiharu Inukai
Inukai fires Asteroid through a firearm of the assault rifle type resembling a personal defense weapon, which is smaller and seemingly wielder, allowing him to aim more accurately. He appears to be very skilled and experienced with it, being able to shoot while in move and even while holding it with a single hand.[7]

Hiro Kitazoe
Satoshi Mizukami
Mizukami Asteroid
As a member of a top tier unit, Mizukami is quite efficient in using Asteroid. He first used it in Chapter 157.

Takuma Yuba
Yukari Obishima
Kazuki Kurauchi
Yōko Katori
Katori Asteroid
As an All-Rounder, Katori can get fight at close quarters and swiftly pull out her handgun to shoot opponents nearly at point-blank range,[8] although she can also hold her own in a firefight at mid-range.

Rokurō Wakamura
Wakamura Asteroid
Wakamura fires Asteroid, his primary offensive Trigger, through an assault rifle.[9] He is capable of casting Shield around it, so as to shoot while protecting himself.[10]

Tatsuya Kuruma
Kuruma Asteroid2
Kuruma's main offensive Trigger is Asteroid, which he fires through an assault rifle. He is adept at switching from offense to defense and vice versa, and is capable of firing from behind Shield.

Wataru Urushima
Kōtarō Suwa
Suwa Asteroid1
Suwa's main offensive Trigger is a shotgun loaded with Asteroid bullets. It has high firepower and, due to the number of bullets fired at once, it is difficult to avoid at close range, but its accuracy decreases at mid-range. When Bagworm or Starmaker are not required, Suwa can double his firepower by using two shotguns instead of just one.

Daichi Tsutsumi
Tsutsumi shotguns
Tsutsumi's main offensive Trigger is a shotgun loaded with Asteroid bullets. It has high firepower and, due to the number of bullets fired at once, it is difficult to avoid at close range, but its accuracy decreases at mid-range. When Bagworm or Starmaker are not required, Tsutsumi can double his firepower by using two shotguns instead of just one.

Rei Nasu
Kuniharu Kakizaki
Kakizaki Asteroid
Kakizaki wields an assault rifle loaded with Asteroid bullets. He is capable of shooting while on the move.[11] He seems to be quite accurate, hitting Wakamura's shoulder multiple times in spite of the latter moving and having put up a Shield.[11]

Fumika Teruya
Teruya Asteroid
Teruya fights using an assault rifle loaded with Asteroid bullets, which grants her a higher rate of fire compared to other firearms.

Kotarō Tomoe
Satoru Hayakawa
Ryōgo Funabashi
Hitoshi Matsushiro
Yūichirō Yoshizato
Hidetaka Kitazoe
Keizō Mamiya
Mitsuya Koinuma
Takahiro Ebina
Makoto Chano
Chano Unit Asteroid
Chano dual-wields handguns loaded with Asteroid bullets in combat. He has the same Trigger set as Fujisawa to improve coordination.

Itsuki Fujisawa
Chano Unit Asteroid
Unlike his captain, and despite having two handguns in his Trigger set, Fujisawa uses only one at a time. He has the same Trigger set as Chano to improve coordination.

Waka Utsunomiya
Osamu Mikumo
Osamu Asteroid
Asteroid is Osamu's ranged Trigger. He generally divides the trion cube in 27 pieces, but he has also fired it whole to maximize his output. His bullets are not very powerful due to his low amount of trion, although they can still effortlessly damage a trion body. When fighting alongside his teammates, he uses them to create disturbances and control the position of the opponent, using his excellent strategic abilities. He is also capable of reprogramming the Trigger's parameters to adapt to the situation. His skill was originally very poor, but after training under numerous A-Rank agents, his accuracy improved and he learned to scatter his bullets to increase hit probability at short range and attack from multiple directions at once, as well as to delay his shots in order to catch the target unawares after luring them in position. Osamu was first seen using Asteroid in chapter 12 (episode 6 in the anime).

Slow Buckshot (低速散弾(ていそくさんだん) Teisoku Sandan?):[12] Osamu scatters numerous, small rounds of Asteroid bullets around himself, making it difficult for the enemy to maneuver or attack without coming in contact with these bullets. The power/range/speed ratio is 70/29.9/01.[13]