Play Sentouin - Yamada Hajime (j)(rising Sun) Online

Sentouin: Yamada Hajime was a Japan-only release for the Game Boy Advance, published by Rising Sun. It came out during a time when the handheld was full of experimental titles, especially from smaller Japanese developers. You don't see many people talking about it now, which is a shame because it has a specific kind of charm.

You control Hajime Yamada, a soldier navigating a series of side-scrolling stages. Your main goal is to fight through each level, defeating enemies and confronting a boss at the end. The gameplay mixes run-and-gun shooting with close-quarters melee attacks; you can switch between a standard firearm and a sword on the fly. A key mechanic is the ability to command a small, hovering robot partner that can attack independently or be directed to specific targets. The levels are compact but demand careful movement and quick weapon swaps to handle different enemy types. It feels like a brisk, challenging action game where you are constantly making small tactical decisions.