Ill use Shadow The Hedgehog as an example.
- In one of the final boss fight Shadow says 'Game Over Sonic' which could be a reference from Sonic Adventure 2 where Sonic says 'Game Over Shadow' in the Hero Story, but didn't Shadow have Amnesia?
- At the beginning of the game and the intro Shadow can be seen standing in a full moon, but wasn't the moon destroyed almost into half by Eggman in Sonic Adventure 2.
- At about before stage 3rd level scene we see 'The President' with a picture of 'Sonic' and 'Shadow' together saying that they both had saved this planet, but how could this picture have been taken if Shadow fell from the orbit and hasn't been seen for some time or presumably dead.
Sonic adventure 2 - Fall from the orbit and live'