Deus Vult II: You want a masterpiece? This is it. Super-maps like none other, and he even threw in the smack-down for Belial by allowing him (or anyone who wanted to) to run through DV 1 again at the end. My only nag was that when the last level with gameplay, Hell's Vendetta, was over... I think he could have personally thrown in one more extra hell-themed map. That's just my opinion though.
And if you really want to up the extremeness of it, throw on a weapons replacement wad or any sorts. Whether it be WildWeasel's, DBThanatos', Xasers, it doesn't matter. It's still pure genocidal fun. Many of the new maps will be much harder/easier, depending on skill level, than the original Dues Vult. Mind you, if your game lags, try disabling GL lights in GZdoom if you use it, and fog. (Found out the hard way with AEoD...)
Like DV1, you must be able to withstand lots of killing and managing monsters more carefully. The Unholy Cathedral is a righteous clusterfuck if you get far enough.
Download it from Doomworld.
