[hype noises]

If this isn't evidence enough towards making the Grinch leak more credible, I don't know what will.

Isaac was an AT in Brawl, he was removed in SSB4, now suddenly there's a Golden Sun item in SSBU. If I'm not mistaken, an AT is more of a big deal than a plain old item because legit characters appear. I doubt Sakurai took Isaac out of SSB4 only to put him back in as an Assist Trophy. And if Golden Sun were to only be represented by one measly item, that would certainly rustle the jimmies of many fans, whether of Golden Sun or leak believers.