Mega Man at its very core has always been about options. Selecting stages in any order you want, using whichever special weapon you prefer, etc. Mega Man Zero 3 encapsulates and achieves that tenfold. You're offered so much variety from your weapons skills, enhancement chips, cyber-elves, combo system, and how you approach stages and bosses that the replay value is practically endless. There are some serious balancing issues sadly, and the game is noticeably easier than the other Zero games. But top the unlimited variety with mostly fun levels, an amazing story, and great spritework and music for the GBA and you have what amounts to what I'd easily call the best Mega Man game. ...And what plenty others agree with nowadays.