Raiden

Raiden (1990) is a legendary vertical-scrolling shoot 'em up (shmup) originally developed by Japanese developer Seibu Kaihatsu. While it debuted as an arcade hit, its popular MS-DOS conversion brought high-octane arcade action to home PCs in 1994.
Set in the year 2090, Earth is under a sudden, massive invasion by an alien race known as the Cranassians. Earth's military forces build a super-fighter jet based on captured alien technology: the Raiden Supersonic Attack Fighter (the Raiden-MK II).
Playing solo or with a second player in co-op, you pilot the fighter jet across 8 stages—ranging from countryside battlefields and military bases to space stations—to eliminate the alien threat.
Raiden codified many design tropes that defined 90s vertical shooters:
Primary Weapons (Color-Coded Power-Ups):
Red (Vulcan Cannon): A wide, spreading bullet spray ideal for clearing large waves of smaller enemies across the screen.
Blue (Plasma Laser): A concentrated, continuous beam dealing massive damage to heavily armored targets and bosses.
Secondary Weapons (Sub-Missiles):
Nuclear Missiles (Yellow 'M'): Slow, high-impact explosive rockets.
Homing Missiles (Blue 'H'): Faster, auto-targeting missiles that lock onto individual targets.
Thermonuclear Bombs (B): A screen-clearing emergency weapon that deploys a massive explosion, wiping out weak enemies, canceling incoming enemy projectiles, and dealing heavy area damage.

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