Re: All credit to iD games...
So many of us experiencing identical flashbacks, especially the Dragon 32 to Amstrad 464 (and then 6128).
Serial cables at the dining table were a thing at mine for while but soon I scored for some old cheapernet cards and hooked up a small token ring. I may be wrong but I only recall up to four players on head to head and can't recall internet play, but that might have been the limitations of my setup back then.
I do recall LAN parties involving mates bringing base stations, CRT monitors, Soundblaster speakers / headphones, keyboards and mice for a whole weekend. Used to flip between Doom, Quake, Duke 3D, Heretic and Rise of The Triads.
Ah the chicken spell in Heretic. Halcyon days.....