this is one of those games that is a really really cool idea on paper but executed badly
it's not because "oH sHaDoW iS eDgeLoRd GuNnY hAhAh", the level designs are simply not cut out for Shadow's physics, the game can lag immensely (guess that's just a PS2 thing), the alignment system is also really cool, but it gets annoying when you meet a hero or dark character and it seemlessly switches level objectives without you realising
that's another thing I find weird about this game, the alignment objectives are fucking wack
Most Hero objectives are just "oh find this key or flip this switch and you're good haha", but with the Dark objectives, it's tedious shit like "go back into the level and kill every. single. enemy." or "oh haha flip this switch and flip this other one and this other one" it might just be me but for a sonic game it's annoying
granted, the guns are fun to use and control, the cutscenes in this game are pretty good (bar the weird voice lines and excessive use of the phrase "disgusting black creatures")
and the 2-player battle mode is some good fun
overall it's not the worst thing ever, but it's not that good either