An absolutely top-tier side-scrolling action game, Astro Boy will both enthrall and challenge the most seasoned gamers.

User Rating: 9.4 | Astro Boy: Tetsuwan Atom - Atom Heart no Himitsu GBA
Treasure, the master developer of side-scrolling action, has done it again with Astro Boy: Omega Factor, a game which manages to kindle a nostalgia for the über-tough shooters of the eight- and sixteen-bit eras, and to amaze with the ability to deliver such a stunningly beautiful game on a handheld platform. The thought put into the control of Astro Boy is phenomenal, which is the reason I put the learning curve at 30-60 minutes, because despite its efficient training quasi-mission, the uses for many of Astro's functions can be polished during gameplay. A shining example of this is Astro's ability to dodge enemy projectile attacks using his jets, since Astro Boy can - and often needs to - plow through hordes of enemies, and can do so with a minimum of damage. There is no doubt that this is one of the best games in the GBA library, and for raw challenge, action and portability it is unmatched. If you have waited for a quality GBA title, whether you're a fan of old-school side-scrollers, jaw-clenching challenge, gorgeous sprites, or all of the above, pick this up now.