
The next time he shows up is his infamous fight with Yoshi, almost killing the poor dinosaur to get the Chaos Emerald (and says that he would have killed him anyways even if he simply handed the gemstone over). Once he makes it to the Mushroom Kingdom, he wastes no time slaughtering a Goomba simply because the poor sod didn't give a Chaos Emerald to him (and it wasn't like the Goomba could have known what it was anyways).

This does nothing to deter him from chasing after the Chaos Emeralds, which end up in the Mushroom Kingdom along with the two hedgehogs. He sets out to collect all seven Chaos Emeralds and kills everyone who isn't named Sonic, Shadow, or Eggman, turning more than half the planet into a burning wasteland in the process, and nearly kills Sonic, only being stopped from doing so by Shadow showing up in the nick of time. He's not done proving to the viewers how nightmarish he is, oh no.

Seeing the damage he's wrought triggers a thirst for power and a lust for destruction in him and he becomes the villain of the first season. Mecha Sonic survives the event, even without a single Chaos Emerald. The result is life becoming completely unsustainable from the impact and explosion, but wait, there's more. Not long after his creation, he destroys the Death Egg (Eggman's moon-sized base of operations for measure) and forces it to crash land into Mobius.

For one, he's Metal Sonic combined with other Sonic robots. Turbo Mecha Sonic himself is the epitome of this trope, FULL.
