

How well multi-player works.
If it is coop, like in Bubble Bobble(1986), that needs occaisional partner assists or straight-up player saves.
Or competitive, like Wipeout 2097(1996), which has excellent catchup mechanics.
Or larger scale competitive, like Quake1 shareware(Qtest) at 16-player.
Each of these showed examples of quality play-testing and balancing, making for enjoyable player interaction.
These days, Cube2:Sauerbraten shows top coop and competitive play in the one game, with insta-CTF interactions largely being good, due to the high quality of sight-line polishing in the base maps.



































I downloaded all of the ones on Wikimedia, and tried them out.
Looks even better when viewed on a tablet.
Some images will not load in Panoramicon, because they are not the right rectangular proportions. I think I recropped some of those so that they would load.