Gladiator type mods

Ok so i was wondering, are there any old roman (or w/e era they were in my mind is blanking me at the moment) gladiator type mods out there right now? Basically in a pit and monsters walk in through gates and they get progressively harder and harder? or well something along those lines?
I've looked everywhere for something like that and i can't find anything.
Thank you :)
Orion

Skulltag. It's one of the default game modes.

As a vanilla example, probably Hell Revealed MAP31.

Yeah, Skulltag's built-in invasion levels are pretty solid. Other invasion stuff worth checking out includes Armageddon 2 and Ultimate Torment & Torture Invasion. Also, if you want more single player friendly or smaller scale stuff, I would recommend Imp Arena, Imp Atak* and for extremely minimalistic one-on-one fighting, Survival.

*I know it's a shameless self-plug, but the level itself was a relatively popular arena map back in the day.

Ok cool thank you I will have to check them out :D
I would make the map myself but unfortunatly i have a mac :( my PC crashed completely and Doombuilder won't work on my mac :(