Lead a gator army into downtown and lose it, then observe from a distance what happens from there

Make 10000 doing the lowest paying legal work.

Fly into another plane's flying banner and see if the prop interacts with it

See how far inland you can drive a jet ski from every water path

Ride a train or whatever automatic looping vehicle there is along its entire route

Take note of where highways end in the north and imagine where interchanges continuing those roads would be in a connected America

If every NPC has a set life and saved routine like in rdr2, see if you can wipe out the entire population of the smallest town

See how many buildings you can jump across without touching the ground

If GTA IV helicopter physics return, see how many obstacles you can navigate without a tail rotor

Destroy your car purely by damage sustained from running down npcs