Below is my copy-pasted explanation of what is going on in this WAD and why it looks like this:

 A month or two ago, I decided to shove an incomplete, single page PLAYPAL lump into a WAD and discovered that this does not immediately cause the game to crash, but rather massively screws up the pain, pick-up, and radsuit palettes. Through further testing (big thanks to @Rayziik and @ryiron, later @Doomkid for double-checking dosbox behavior was consistent with DSDA-Doom's software renderer), our understanding became that these blank pages were instead being filled with garbage data from system memory. What this means is that while the palettes have the general theme of getting darker as you stack pick-ups or take damage, the color scrambling that also occurs is different each time you close and restart the port. You can see this relatively easily thanks to the forced berserk pick-up in Map01.

 

Inside the WAD there is a single page PLAYPAL lump with a radically altered palette. There is also an OLDPAL lump, which was a leftover from various futzing around and attempting to figure out the palette behavior. There are also a bunch of colormaps that I made exclusively for use in Map03. These are what causes the seemingly random palette shifting even when you are not picking up things or taking damage. The "blinking" effect in Map03 is the infinite BFG voodoo setup rolling the player over a stack of cells. The "closing your eyes" effect at the end of the maps is a voodoo picking up a radsuit.

 

This palette scrambling has different behavior based not only on the rendering mode you are currently in, but also the mode you are in when the port starts. I ran into issues with opening the port in OpenGL causing the tinting for pick-up and radsuit palettes to be radically different, ruining the fade-to-black and "blink" effects. This is thought to be caused by OpenGL not doing the thing that software rendering does, where it forces an all black value into the palette. Firing the BFG after opening the port in OpenGL would also crash 100% of the time, making it unusable. This is why there is a warning specifically about having to open the port in software initially. There are potentially more quirks to this that I have not ironed out yet, because testing them has been very confusing.

 

The noisy textures are just noisy textures that get further futzed by the colormaps and pain/pick-up palettes, resulting in hundreds of different unique "palettes" every time you close and restart the port.

 

edit: All of the monster sprite frames are also reverse-paletted on every other frame, just for increased noise and color fuckery. 

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below are some further points of interest posted by Shepardus:

Thanks for the writeup; I remember seeing a post here showing a similarly crazy effect from taking negative damage, and was wondering if this WAD used that. This is different, but sounds similar in that it uses garbage data as the palette. I'd also add that the colors vary by port, and probably also the specific build of the port too. In Woof, restarting the level using in-game restart also scrambles the colors, while in dsda-doom it does not. 

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you can find this original context in the Doomworld release thread:
https://www.doomworld.com/forum/topic/144100-i-will-never-give-you-any-thing-mbf21-umapinfo/
