Board Thread:General Discussion/@comment-26006155-20190617222636/@comment-26006155-20190728234942

We don't know for sure The Darkest Experiment itself is what shattered Gaster.

Whatever dark experiment Gaster was planning, Alphys did something different. Her Entry 17 is about the Amalgamates, and her approach to the situation was different.

The followers do think that Alphys can share the same fate, though. Even though the time for following Gaster's footsteps with The Darkest Experiment seems to be in the past.

Whatever event happened, a time/space portal was involved. A portal that is still down there.

If Gaster's memory was erased from the world, that wasn't an accident. It means that somebody repeatedly killed him, and reloaded their save. A very deliberate, repeated act.

That's why I think Sans tried to prevent The Darkest Experiment, by killing Gaster. First in the Alpha Timeline, then earlier and repeatedly in the Beta Timeline.