Board Thread:General Discussion/@comment-28974149-20180305043309/@comment-32182236-20180324110336

Actually, Toby IS a "dirty liar". He said the v1.0001 patch would only fix bugs. This was not the case, it added in secrets as well.

So, we can't say there's proof of Undertale 2 coming. (Of course, we can't say this DISPROVES Undertale 2 either.) Besides, we already know quite a bit about Gaster, and there's still evidence sprinkled around for us to find out even more. Since falling into his own creation made him shatter, we can clearly deduce he created more than just the CORE (either that or the CORE is/was much more than just a powerplant.)