Thank you Dragon32! Yes, looks like New Blood is the mod. I had scanned over the MGSO mods on the wiki credit list but for some reason New Blood isn't on there, so I was stumped on which mod it was. I should have looked over my actual mod list as well. It was definitely installed by MGSO.
So, I downloaded New Blood from MMH and I'll post the relevant parts of the readme here for those that might be running into the same problem:
Spoiler To install this plugin, extract the Texture folder into your Morrowind Data files folder. I have also included two alternate versions of the stock red blood and metal spark hit effects. They are an improvement on the Bethesda textures in my opinion, but you don't have to use them if you don't wish to. They are located in the Alternate textures folder. Simply copy the textures out of the Alternate textures folder directly into Textures folder in you Morrowind Data files folder. Be warned that these will overwrite or replace the stock Morrowind hit effects.
The second part of the installation will require you to modify your Morrowind Configuration Settings file.....or this mod will NOT work as intended. Using MS Notepad for this should suffice. Open the Configuration file and scroll down to the [Blood] heading. Insert the following text under the [Blood] heading:
Model 0=BloodSplat.nif
Model 1=BloodSplat2.nif
Model 2=BloodSplat3.nif
Texture 0=Tx_Blood.tga
Texture 1=Tx_Blood_White.tga
Texture 2=Tx_Blood_Gold.tga
Texture 3=Transparent_blood.tga
Texture 4=CBbug_blood.tga
Texture 5=CBoil_blood.tga
Texture 6=CByellow_blood.tga
Texture 7=CBstone_blood.tga
Texture Name 0=Default (Red)
Texture Name 1=Skeleton (White)
Texture Name 2=Metal Sparks (Gold)
Texture Name 3=No Blood
Texture Name 4=Bug Blood (Brown)
Texture Name 5=Dark Blood (Black)
Texture Name 6=Yellow Blood
Texture Name 7=Stone flakes (Gray)
---Now save your Config setting file and exit Notepad---
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2. PLAYING THE PLUGIN
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From the Morrowind Launcher, select Data Files and check the box
next to the "NewBlood_MW" esp file for use with Morrowind only, or check the box next to "NewBlood_MwTbBm" for use with Morrowind, Tribunal, and Bloodmoon. Do not use both at the same time as it will be redundant.
This mod introduces several new blood types into the Morrowind game engine, allowing for a wider variety of hit effects for different creatures (and NPC's) during combat. I have included two ESP files that reassign the hit effects/blood types for various creatures ingame. I have not altered any of the creatures that are flagged as Blocked in the CS.
But the beauty of this mod is that once the textures are installed and the Morrowind Config file is properly altered, the new blood types will be available in the Construction Set for any mod you wish to use them in. So even without using the included ESP files this can still make a good modder's resource.
It's also very easy to introduce your own blood/hit effects using the same Config file alterations. Just be warned: the game engine only allows for a maximum of 8 effect types total. There are the three default types, and then there are the 5 new ones I added via this mod. To add other types you will have to replace some or all of the types included in this plugin.
So I guess I will have to look it all over and decide which blood textures I want. The readme says that only 8 different types are allowed by MW. Is it possible that this could be increased by the MCP allowing for more diversification? If so I could post the suggestion over there.
EDIT: Okay so it looks like, just based off the .tga names (e.g. PLX_CBbug_blood.tga vs. CBbug_blood.tga), Piratelord may have used the same textures, but just added PLX to the tga as a prefix for his own organization purposes. If this is the case I'm hoping the only potential incompatibility is assignment of textures to creatures, and inclusion of all the textures between the two mods is no longer an issue. As long as the numbers used to register them in the ini are irrelavant to the actual implimination in game... *crosses fingers*