Irresponsible/dickish elder race ideas

Looking for some interesting/funny things for an irresponsible/dickish elder race to do. I’m setting up a sci-fi world builder where humanity was the elder race and left behind tons of weird stuff. So far I’ve come up with the following.

-Left ringworlds and Dyson spheres.
-Created a bioweapon but never disposed of it afterward.
-Sent robots time traveling into the future to gather samples (the robots attack the players on contact).
-Removed a plane of the universe from existing.
-Uplifted civilizations in ways that screw over the uplifted.
-Bioengineering monsters and other things.
-Detonated various celestial bodies in weapons tests wrecking nearby areas.
-Intentionally terraformed a planet to be the biggest hellhole possible even though there are nice minerals there.
-Left weapons of mass destruction sitting around.
-Trapped robots on a planet to see how long it would take them to get through the acidic atmosphere. Robots hate other sapients now.
-Decided that magic should be a thing and created a force of physics that controls it, but made it ridiculously complicated and easy to mess up.
-Opened an interdimensional gate, shut it when horrors from beyond showed up, didn’t bother to demolish the gate.
-Started building a giant galaxy-wide network of automated defenses that stop combat of any type but get bored and stopped leaving it halfway constructed.

Anyone got more good ideas?

Made a tool for creating black holes and just left it lying around some place.
Installed a bunch of enormous engines on a moon and made it propel into space. The catch is that many teleport stations actually redirect to it.
Created a technological virus that decimates all tech and sends civilizations back into the Stone Age once they surpass a certain level of sophistication.
Put huge monuments of themselves on planets with primitives so that they would be worshipped.
Made archives of knowledge disguised as 'holy books' so that everything in them came true, up to a certain point, after which they devolve into nonsense.
Left a station full of artifacts and technological marvels, made it orbit just near the horizon of a supermassive black hole.
Created portals that have a 50/50 chance of leading either to a paradise world, or the surface of a star.

-creates perfect Gaia world with all creatures on it being mostly harmless, rare rescources a plenty and soil being fertile.buut they got lazy and to keep the animal population down they just made a virus that kills every sentient being on the planet every couple of millinia.the virus however is left alive and randomly evolves over the next millinia into the variose creatures It killed, restarting the cycle over again.

Created a race of living ads

>Painted a massive ad for fast food on the moon of a primitive planet
>created new reality tv by watching primitive planets then turning that in to shows
>created giant space monsters just cause

Isn't this basically the plot for Metroid: Fusion?

-Had a race who's whole purpose was to be their personal slave labor force. This race has since their departure have decided that they or this elder race's spiritual successor despite being designed to be unable to truly comprehend their technology and it's ramifications and have poor critical thinking and decision making abilities. They still have a massive juggernaut of an empire because they started out very numerous and their high breeding rated have kept them from going extinct thus far.

A thing I am doing RIGHT NOW is compiling and feeding as much madness as possible to a learning AI in order to make a madness engine.

So, you can use that. I feel it is all of our responsibility to leave behind personal horrible elder race artifacts.

>Painted a massive ad for fast food on the moon of a primitive planet.
I'll describe it to the player in the vaguest terms possible so that they'll have to decode the words on it. That should be funny.

Sounds like the results of the last campaign I played in. Except the players were inside the simulation and were manipulating things to produce glitches to exploit the situation that increasingly fucked their reality but eventually got them to escape the simulation and into the wider system.

Turns out this was intended, the party learned a simplified set of all reality, good work ethic, and individual action capacity with the ability to self modify through the bullshit they did. So now they've got jobs as AIs to these elder race fuckers but by and large are ok with it because 'at least we're in a higher reality.'

>The epilogue is they're working to figure out if they can hit the next stage of reality because this is probably a simulation as well.

"Be sure to drink your Ovaltine!"

>it's a giant pair of arches made from enough gold flakes to bankrupt an entire solar system, scattered into the soil of Mars' northern hemisphere, setting up the pattern so it can be seen from orbit

>Year 100k A.D.
>A Human tourist accidently dropped a Quantum-antimatter powered holoimager while sight-seeing native Dinosaur-analogs on Sigma-IX
>50,000 years later was discovered intact by Iron-Age level Dinosaurid society
>Led to ultra-rapid tech development but without the usual sociological advancements
>Space Gigantic Dinosaur Mongol Hordes that consumed the entire NGC 185 galaxy.

>Figured out a way to prevent the heat death of the universe: get rid of the dark energy driving the universe's expansion
>To do this they created a gigantic device that vents dark energy out of this universe and into another
>Now some really pissed off species from another universe have finally found the asshole reality that's accelerating their death by entropy

And now I have a good final battle for the campaign.

That's Futurama level of irresponsible.
Was Zapp Brannigan their emperor?

-Massive techno-vault meant for uploading biological consciousnesses into digital storage. There's no synthetic bodies to upload the consciousnesses to or anything, it's just for storage. Which is empty. But the automated uploader devices are ready and waiting for an explorer/victim to find them.
-Intergalactic zoo hosting interesting and often deadly animals from all around the universe. Automated and isolated from its surroundings. Deals with overpopulation of hosted species by dumping the excess critters outside.
-Automatic mobile borehole driller. Due to a malfunction, each hole it bores is a bit deeper than the last. Planet it's on is already rather full of holes, yet it's only a matter of time until it too-deeps the entire planet.
-Planet that has been turned into a landfill. Mountains of ancient trash cover the entire surface. Barely functional space station on a stable orbit contains both docking bays for ships, and dumping bays which drop everything in them to the surface at regular intervals. Which is which is rather poorly marked.
-Asteroids attached together to form a crude penis shape.
-Planet which has its entire core turned into a massive geothermal power plant. It has a simple and effective off switch capable of effectively killing the entire planet.
-As above, only someone has already pressed the switch. Cold, dead world with no or a fucked up magnetic field. Power plant's control station repeatedly broadcasts the message "Please reboot planet to continue".
-Combination of space elevator and roller coaster. It works, but cargo needs to be able to handle 7 Gs to get up intact.
-Uplifted plants that are very intelligent, but incapable of moving and lack the limbs to use tools.
-Single-use space colonies. Disposable stations originally meant for vacation use and to be discarded or recycled after. After being activated they work perfectly for a while, and after a set time run out of power and/or start breaking down.

>altered the orbit of several planets and their moons in a system for their version of the Olympic games with catastrophic long term effects on the system in question.
>As a social experiment created a device that would periodically block all light from the local star to a planet inhabited by a developing race for one day and observed the results. They never packed it up when the esperentire was done.

I'm reminded of the Legacyverse.

They abducted Humans, then bred and/or genetically engineered them to be 6 inches tall and used them as living PDAs and pets.

Tell me more about this game. What system was it? How did the glitches work?

>a small cluster of stars cordoned off to be a weird mix of an MMO and a hunting reserve
>in the ages since the service shut down, the "NPC" AIs and genetically tricked out beings have just sort of kept on doing their thing

that picture is brilliant

>In order to fix an overpopulation problem, developed an advanced AI with a super-weapon that would determine which people would be missed the least. AI is now insane and just zaps people across the galaxy at random.

remodeled and welded together several planets into the shape of a cat thru orbital bombardment

Whether or not that cat still looks like a cat depends on how long humans have been dead for

A few AI-based ones.
>Created several series of autonomous space mapping probes, which harvest raw materials and autonomous craft of a different series to make new probes of their type.
>Created an autonomous clean-up crew to eliminate any precursor derived technology - unfortunately, their definition of technology is extremely vague, and includes all spacecraft.
>Stress-tested various strains of AIs. The tests never stopped.
>Uplifted plants that have found a way to puppet meat-bodies.
>Engineered plants that spread via cannon-fired seeds launched at escape velocity.
>Autonomous harvesters stock a giant galactic council, abducting one random person from each planet to provide suitable representation for a year, then wipes their memories and returns them.
>Turned a planet into a spacecraft factory. It still runs, but has various quirks in ship design.
>Engineered a planet into a raw material foundry. It has a giant mouth, and engines on the back that work by firing the raw materials at high speeds.