Play River City Ransom Online

River City Ransom came out on the NES in 1989 from Technos Japan, the same folks behind Double Dragon. It was a side-scrolling beat 'em up, but it stood out from the crowd by mixing in some light RPG elements, which wasn't all that common for the genre back then.

You control either Alex or Ryan, high school students who have to fight their way through waves of enemy gangs to rescue Ryan's kidnapped girlfriend. You move screen by screen, clearing out thugs with punches, kicks, and weapons you can pick up, like lead pipes or trash can lids. Defeated enemies drop money, which you use to buy food, books, and other items from shops to permanently increase your stats or learn new special moves. The pacing is brisk, though some sections can feel grindy if you need to farm cash for upgrades. It feels scrappy and satisfying, like you're really building your fighter from the ground up through every fight and purchase.