Tear Jerker / Gaming All-Stars

• At the end of "City in Chaos", Sonic returns from fighting Perfect Chaos before noticing someone missing from his group: His friend Tails, who had been walloped into the distance by Lizzie. When he asks Alex and Cole what happened to him while he was away, they give no reply since they were too busy dealing with their own problems to notice his disappearance. While the fox and hedgehog do reunite in the series' final moments, this short scene is still rather melancholy given Sonic and Tails' friendship.
• The entirety of "The Aftermath", which deals with the wreckage of the city Sonic and his friends were located in, having been nuked by G.U.N. at the end of "City Invasion". The establishing shot of the corpses and trophies lying around the premises just before Marcus Fenix arrives is enough to make this episode hard to stomach.
• The Heavy's death by way of Polygonization. Not only is the strongest member of Mario's group no longer with them, but now they're forced to fight his reanimated body (Which given his immense physical stamina, is no easy feat). It serves as a chilling reminder of what Polygon Man is capable of, and a stark hint toward his role in the forthcoming finale...
• The series finale puts the previous examples to shame: A good way into the ultimate battle, absolutely everyone involved in the campaign except Mario, Sonic, and Crash are either dead or polygonized, and the monster apocalypse rages on through the night. Master Hand and Crazy Hand, having broken free from Polygon Man's hypnosis, are motivated to create a Subspace Bomb to destroy the moon. While this does mean that it will eliminate Andross, it also means that the remaining heroes will be swallowed up by the explosion. However, it's slightly less heartbreaking in Remastered because of the sequel hook leading into the events of 2 via Mario, Sonic, and Crash's resurrection.

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