>>7972221>Where did you get those cool gog-style icons?GOG.
For some of those games (e.g. Blood and PowerSlave), I actually got the game files from the GOG releases, and so they naturally came with those icons. Some others (e.g. the Steam version of Doom) came with shitty icons that I hate, so I replaced them with the nicer GOG icons, which I downloaded from the GOG image servers.
The other guy
>>7972341 is probably right that you can just search "_____ GOG icon" and find them, but I basically went straight to the source by way of GOGDB.
>go to https://www.gogdb.org/>search for game and click result>go to "Details" tab>scroll to "Icon">click the link to a https://images.gog-statics.com/... URL>it's a shitty JPG icon>change ".jpg" to ".png" in the URL>it's a nice PNG iconAs for the Quake icons, those were installed to my system's icon folders when I used GameDataPackager to set up the Quake games and their mission packs for QuakeSpasm. If I change my icon theme, I can actually get different Quake icons, but in general I prefer the icon theme I'm using. GOG actually does have nice icons for the Quake series...
>https://images.gog-statics.com/b11ccc5301d841d7062cc3a46f88d163076ef22a9bd6ebce5b8eab89bea323a0.png>https://images.gog-statics.com/bc945e7a81d859ce04e31c73497cd4d48f93f2bf25d312c882b247d9b679e6fc.png>https://images.gog-statics.com/62f02ff278135823323adb3f5f353e4b8d948da1619e519cd6966491fdd62fb4.png...but the ones shown in the screenshot are basically just from some Mint/Ubuntu/Debian repository.
As for the Marathon games, those are the icons you'll get if you download the Windows releases here:
>https://alephone.lhowon.org/Oddly, they don't seem to be included in the game data they distribute for use on Linux — they're just embedded in the Windows executables (which you can extract on Linux with wrestool if you really want to) — but you can find the same icons online if you search around.