Got Serpent RPG, any other good mods out there?

[ULTRA]

Preferably ones that work in coop?

[Emmanuelexe]

I think these can work in coop, but you have to setup it with zandronum (doomseeker) and configure it with TSPG servers...
Hexen:
HeXmas Special
https://forum.zdoom.org/viewtopic.php?f=42&t=62375
The Land of the Serpent Riders:
https://www.moddb.com/mods/hexen-iii

Hexen Upstart Mapping Project
https://www.doomworld.com/idgames/levels/hexen/v-z/xump

Resurrection of Chaos
http://www.moddb.com/mods/resurrection-of-choas

Shadows of Cronos
http://www.moddb.com/games/hexen/addons/hexen-shadows-of-cronos

Wolfen
http://www.moddb.com/mods/wolfen/downloads/wolfen

Scourge of Vicerus
http://www.moddb.com/mods/scourge-of-viscerus/downloads/scourge-of-vicerus

Necrosis
http://www.moddb.com/mods/necrosis

Tower Of Chaos *zdoom*
http://www.moddb.com/mods/tower-of-chaos

A New World
https://forum.zdoom.org/viewtopic.php?f=19&t=47060

Nadir
http://www.moddb.com/mods/nadir

Shades of Darkness
(cant post here)

Battle for the sphere of chaos
https://www.doomworld.com/idgames/levels/hexen/a-c/bftsoc

Some could bug or block some players since it uses script who close some doors, not sure.
For normal maps, you have to setup the command who allow players to go through the other players without telefrag kill them, it allows the respawn in the same start spot without killing the other guys, specially at the beginning of the maps, because some maps put 1 player start and not 3 or more.

If you want, we have a facebook group to talk about it (+600 people)
https://www.facebook.com/groups/heretichexen

Have fun