Uploaded August 2026 | Updated September 2026, 3 weeks ago
Developed and published by Irem, Lethal Thunder was released in arcades in 1991, with the Japanese version known as Thunder Blaster. Running on Irem’s M92 hardware, it is a vertically scrolling shoot ’em up with colorful mechanical designs, aggressive pacing, two-player co-op, and one particularly unusual feature: the harder and faster you fire, the stronger your weapon becomes.
Rating: 7.8/10
At first, Lethal Thunder looks like a fairly conventional early-’90s vertical shooter. You fly upward through waves of aircraft, tanks, turrets, and increasingly elaborate mechanical enemies before confronting a large boss at the end of each stage. In practice, though, the game feels quite different from something like Raiden because of its distinctive firepower gauge.
Rapidly tapping the fire button raises your weapon power, producing larger and more destructive shots. Stop hammering the button and that power gradually falls away, meaning maximum damage requires almost constant input. It gives the action a frantic physical quality rarely seen in other shooters: fighting the enemies is only half the challenge; the other half is keeping your firing finger going.
It is both the game's best idea and its biggest weakness. Building the meter while tearing through formations feels extremely satisfying, especially during bosses, but maintaining maximum firepower for an entire run can become genuinely tiring. Using autofire removes much of that physical strain, although naturally it also changes the character of the mechanic.
There are four different weapon types, each encouraging a slightly different approach. These include straightforward concentrated fire, angled or homing-style attacks, wider projectile patterns, and a short-range flamethrower. The variety is useful because certain weapons are noticeably better suited to particular enemy formations or bosses.
A separate Thunder attack acts as your emergency weapon, wiping out nearby threats when the screen becomes overwhelming. Between the selectable weapons, variable firepower and bombs, the combat has more going on beneath the surface than the simple presentation initially suggests.
The campaign consists of seven stages, which puts it around the typical length of an Irem arcade shooter rather than being unusually short. A complete run moves along quickly enough that the game rarely drags, while still giving each stage room for increasingly demanding enemy patterns and large bosses.
Visually, Lethal Thunder is one of its stronger aspects. The M92 hardware produces colorful environments, large mechanical sprites and plenty of animated machinery. Irem was particularly good at making industrial science-fiction hardware look heavy and dangerous, and that talent is obvious here. Explosions fill the screen, bosses contain multiple components and turrets, and the scenery changes frequently enough to maintain visual interest. Retrospective coverage has similarly singled out its dynamic graphics and colorful presentation.
The soundtrack is also excellent. Fast, energetic compositions complement the constant forward momentum, while the punchy explosions and weapon effects give the action plenty of impact. It may not have the instantly recognizable music of R-Type, but the audio fits the game extremely well and becomes increasingly effective in the later stages.
Difficulty rises considerably toward the end. Faster bullets, enemies approaching from awkward angles and increasingly aggressive bosses demand memorization as well as reflexes. Two-player simultaneous play helps make the chaos more manageable and is also arguably one of the best ways to experience the game.
There is an additional incentive to replay it because Lethal Thunder has four possible endings. Your performance during the boss encounters determines which outcome you receive, giving skilled players a reason to attempt more disciplined runs rather than simply credit-feeding their way to the conclusion.
One unfortunate part of the game's history is that it never received a conventional home-console port, leaving it far less familiar than many other Irem shooters. That obscurity is probably one reason it rarely appears alongside the company's better-known arcade releases.
Overall, Lethal Thunder is an underrated and inventive Irem shoot ’em up. Its button-mashing power mechanic can become exhausting, but it also gives the game a personality that many more conventional vertical shooters lack. Strong weapon variety, excellent pacing, colorful M92 graphics, good music, co-op play and multiple endings make it considerably more interesting than its obscure reputation suggests.
It isn't quite an essential classic on the level of Irem's greatest shooters, but for fans of Raiden, Truxton and other fast arcade shmups, Lethal Thunder is absolutely worth playing—especially if you're looking for something familiar in structure but unusual in execution.
Developed and published by Irem, Lethal Thunder was released in arcades in 1991, with the Japanese version known as Thunder Blaster. Running on Irem’s M92 hardware, it is a vertically scrolling shoot ’em up with colorful mechanical designs, aggressive pacing, two-player co-op, and one particularly unusual feature: the harder and faster you fire, the stronger your weapon becomes.
Rating: 7.8/10
At first, Lethal Thunder looks like a fairly conventional early-’90s vertical shooter. You fly upward through waves of aircraft, tanks, turrets, and increasingly elaborate mechanical enemies before confronting a large boss at the end of each stage. In practice, though, the game feels quite different from something like Raiden because of its distinctive firepower gauge.
Rapidly tapping the fire button raises your weapon power, producing larger and more destructive shots. Stop hammering the button and that power gradually falls away, meaning maximum damage requires almost constant input. It gives the action a frantic physical quality rarely seen in other shooters: fighting the enemies is only half the challenge; the other half is keeping your firing finger going.
It is both the game's best idea and its biggest weakness. Building the meter while tearing through formations feels extremely satisfying, especially during bosses, but maintaining maximum firepower for an entire run can become genuinely tiring. Using autofire removes much of that physical strain, although naturally it also changes the character of the mechanic.
There are four different weapon types, each encouraging a slightly different approach. These include straightforward concentrated fire, angled or homing-style attacks, wider projectile patterns, and a short-range flamethrower. The variety is useful because certain weapons are noticeably better suited to particular enemy formations or bosses.
A separate Thunder attack acts as your emergency weapon, wiping out nearby threats when the screen becomes overwhelming. Between the selectable weapons, variable firepower and bombs, the combat has more going on beneath the surface than the simple presentation initially suggests.
The campaign consists of seven stages, which puts it around the typical length of an Irem arcade shooter rather than being unusually short. A complete run moves along quickly enough that the game rarely drags, while still giving each stage room for increasingly demanding enemy patterns and large bosses.
Visually, Lethal Thunder is one of its stronger aspects. The M92 hardware produces colorful environments, large mechanical sprites and plenty of animated machinery. Irem was particularly good at making industrial science-fiction hardware look heavy and dangerous, and that talent is obvious here. Explosions fill the screen, bosses contain multiple components and turrets, and the scenery changes frequently enough to maintain visual interest. Retrospective coverage has similarly singled out its dynamic graphics and colorful presentation.
The soundtrack is also excellent. Fast, energetic compositions complement the constant forward momentum, while the punchy explosions and weapon effects give the action plenty of impact. It may not have the instantly recognizable music of R-Type, but the audio fits the game extremely well and becomes increasingly effective in the later stages.
Difficulty rises considerably toward the end. Faster bullets, enemies approaching from awkward angles and increasingly aggressive bosses demand memorization as well as reflexes. Two-player simultaneous play helps make the chaos more manageable and is also arguably one of the best ways to experience the game.
There is an additional incentive to replay it because Lethal Thunder has four possible endings. Your performance during the boss encounters determines which outcome you receive, giving skilled players a reason to attempt more disciplined runs rather than simply credit-feeding their way to the conclusion.
One unfortunate part of the game's history is that it never received a conventional home-console port, leaving it far less familiar than many other Irem shooters. That obscurity is probably one reason it rarely appears alongside the company's better-known arcade releases.
Overall, Lethal Thunder is an underrated and inventive Irem shoot ’em up. Its button-mashing power mechanic can become exhausting, but it also gives the game a personality that many more conventional vertical shooters lack. Strong weapon variety, excellent pacing, colorful M92 graphics, good music, co-op play and multiple endings make it considerably more interesting than its obscure reputation suggests.
It isn't quite an essential classic on the level of Irem's greatest shooters, but for fans of Raiden, Truxton and other fast arcade shmups, Lethal Thunder is absolutely worth playing—especially if you're looking for something familiar in structure but unusual in execution.
