Shadow doesn't know why he exists. His memories are a complete blank, and no one seems to know where or why he appeared. Suddenly, though, a race of aliens falls form the sky and starts invading Earth. Their leader appears before Shadow, promising answers if he's to collect the six Chaos Emeralds. Despite his depressed attitude, Shadow's already befriended Sonic and pals. He won't show his affection on the surface, but the choice creates an internal struggle over unlocking the secrets of his past and defending the world that's taken him in.
Walking the line between that struggle is one of Shadow the Hedgehog's most interesting gameplay points. See, you don't have a single option for completing each level in the game. Depending on your actions, you'll actually be working in the name of good or evil. In the game's introduction level, for example, you can aid the aliens by destroying Earth's defense forces or follow Sonic's advice and take out the creatures destroying the city. Your choice changes which level you'll play next, how the story advances, and which ending you'll receive. There's no way to actually see everything Sonic Team has designed for Shadow the Hedgehog without completing the adventure multiple times, and by pressing start, it's possible to actually switch between the good and bad objectives on-the-fly.
Though the weapons have been predominately displayed on the box art, screenshots, and artwork accompanying Shadow the Hedgehog, they aren't played up nearly as much when it comes to the gameplay. You'll have a tough time making it through the game without taking advantage of them, but technically, there are only a handful of times where it's required of players to use something other than jump attacks. The game's quirky controls, however, will likely push most to use what's available to them; using the auto-aim functions is typically easier than trying to guess if Shadow will magically lock onto an enemy when you double-tap jump instead of plummeting off the side. For a series deeply rooted in platforming, it's a bummer the platforming sections are actually some of the most frustrating parts of Shadow the Hedgehog.
