Redditor emclouds asked people to ponder:
"You suddenly travel back 100,000 years to a cave that will eventually be discovered by archeologists, what do you write on the wall to mess with them?"
It's A Sign
"Find out the exact person who will discover said cave, figure out their address, write their address with a specific date, watch them freak out all day."
- TheDonutMan55
"then add 'We will come for you'."
- HeyImZhen
Stephen Would Have Laughed
"My sincerest apologies to Mr. Hawking for missing his party."
"It appears I overshot."
- Nyxu
GiphyPlanetoid Revenge
"A model of our solar system, with an arrow pointing to Pluto saying 'the key'."
- lakewood2020
"Arrow pointing to Pluto saying, 'It's a planet!'"
- SuperCerealShoggoth
Perspective
"Draw a picture of Earth from space."
- CarkillNow
"Draw it as Pangea to really confuse them."
- Gandolf794
"Signed: 'Thug lyfe 3.14159265358979323' and add that S symbol from the 90s..."
- DarrelBunyon
GiphyOminous
"If you know the date it will be discovered add 'We will be back for our planet' and put it say 20 years ahead of that date."
- nerys71
Even More Ominous
"We have used the last of Earth's magic to seal away their dimension and leave you this message in the language of your time."
"Proceed no further."
"You must not destroy the barrier."
"If released they will bring the downfall of your species as they have done to ours."
"DO NOT BREAK THE BARRIER"
- YeahButUmm
Oops...
"E = MC2 + (chip off piece of wall)"
- gotwired
"Dark matter is comprised of—(graffiti painted over the answer)"
- NoStepOnMe
GiphyClueless
"Congratulations, you have found the second clue."
"To find the third and final clue, go back to the first clue and read it backwards."
- steeple_fun
We're Not Saying It Was Aliens
"A bunch of stick-figure guys with spears, running away from a flying saucer that's shooting lasers at them."
- Wadsworth_McStumpy
GiphySo, what message would you leave?
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