Sonic 2 Delta is a hack of the original game "Sonic the Hedgehog 2" that has been modified with various changes to gameplay, graphics, and level design. The exact nature of the changes in the game can vary depending on the version or "release" of Sonic 2 Delta, as there have been multiple updates made by different people over time. Some common features in various versions of the hack include altered zones, new enemies and power-ups, and different character abilities.
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