Shinobi by Sega, first released in the arcades in 1987.
Before Ryu Hayabusa reared his head on the gaming scene in Ninja Gaiden, Joe Musashi was the original side-scrolling tough guy. There were plenty of ninja platformers that appeared before Shinobi, but none so stylish, difficult, and memorable.
The first Shinobi outing introduced players to a world where ninjas weren't merely cutesy or relegated to being feudal period pieces - this told the modern-day tale of a man fighting an evil terrorist organization, comprised of all manner of thugs and artillary, and even a bit of the fantastic (cyborgs, Spider-men!) As was typical with sidescrolling far, you'd advance from left to right and dispatch your foes, throwing ninja stars for distant attacks or kicking and punching up close. Rescuing hostages would power you up, and grant you more powerful attacks as well.
The game was well-produced, with a sharp array of characters and levels accompanied by a high level of difficulty. There were even some very pretty bonus rounds to add to the package's appeal (as a NES player, seeing the bonus round shown in the TV commercial made me realize that SMS had quite a technical edge over my chosen console!)
The original Shinobi is considered a time-honored classic by modern gamers, with a decent legacy which followed in the years after. Shinobi himself (or Joe Musashi, if you prefer) became one of the staple "mascot franchises" in older Sega days, as all the games in the series were usually hi-quality and very well-received with their own unique take on the "modern day ninja" theme, which was a little less over-the-top fantastic than what was being presented in the rival Ninja Gaiden games.
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