“You just lost The Game”

Or a variation:

“[Untranslatable] destructed leaving just an asteroid belt. Mars now uninhabitable. Terraforming of Earth seems to have been successful now that the saurian races are eliminated. Trying again.”

“Aim for the stars they said…”

“Please pick up after yourselves. I am not your maid.”

“First”

I like both of the “Earth is our final chance” ideas, but they don’t explain why we find skeletons.

Instead how about the message being “Go back through the portal before it closes!” That’s reminiscent of situations like the first planet found in Stargate: Universe where they learn that there’s a time limit, or the one Star Trek: TNG where they find a potential stable wormhole but Geordi sees it may not be and the Ferengi scientists don’t believe him.

He who is valiant and pure of spirit may find the Holy Grail in the Castle of aaaaaaaaaaaarrrrrrrrrrrrrrrggggggghhhhhhhhhhhhhhhh

“Don’t trust Elon”

Two peanuts were walking down the street. One was assaulted. Peanut.

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(The cool s)

“Fuck Spez”

If you’re here, you probably did a bad job with Earth. Level failed! (Ambient Level failed music)

Drums…drums in the deep. There is no way out.

“People are all the same”