Doomseeker - A doom launcher everyone who has touched skulltag or zandronum knows. Entryway tier.
Zdaemon - An OG source port and launcher where OG doom players are found. Near-bottom tier.
Bestever - An old server hosting site that had branched out to a few doom launchers and their respective source ports. It was discontinued sometime in 2014? Or 2015? I'm foggy on the exact date. Bottom tier. Though the same could be said for any and all other discontinued hosting sites.
Vela Pax - A large-scale mappack that showed a lot of potential, but was left greatly unfinished and has never been touched since. Bottom tier.
Armageddon 2 - One of, if not the most popular invasion wad of it's time. Surface tier.
Satan's Covenant - An expansive but mediocre invasion wad, infamous for its unfair, server-killing difficulty, patchy custom mobs, and godawful final boss. Near-bottom tier.
Zomb-8 - A... just... riveting mod based off the Left 4 Dead franchise. Bottom tier.
Vietdoom - A mod Brutaldoom-ifying a trek through the Vietnam War. Extremely difficult while yet being built more for single player gameplay, so pacifiers for anyone hoping for a casual experience. IDK tier.