A short door riddle

After getting out of that area in the void, going back through the error path, up to the hidden section into the waterfall you notice you came all the way back, here you wonder why this waterfall has so many secrets, You nod at Eclipse and you start to run and climb up the waterfall, it was grueling but after attempts after attempts and after attempts you finally reach the top, you then notice that those red creatures from before aren't trying to attact you, but are instead waiting for you, some even nodding or bowing. You are confused but don't question it, as you turn around you see a massive door that you couldn't have seen from before. Open it?