LogFAQs > #985483565

I don't think they were intentionally trying for that, but they ended up with similarities. I think I read Shadow was originally intended to be a one off character in SA2 but became so massively popular they brought him back from the dead.

Sonic ended up being basically a genetic miracle, having super powers for seemingly no reason from nowhere, keeping up and sometimes surpassing Shadow who is a living weapon created from the DNA of a nearly immortal galactic conqueror.

Keep in mind, Vegeta was not portrayed as being anywhere near Goku's strength until Dragon Ball Super, which came out way after SA2.

Before then he was always portrayed as an arrogant loser who was always chasing after Goku but could never catch up because Goku was just that much more naturally talented than him.