This mod adds bloodier combat effects to the game and includes some blood splats similar to those removed during the classic beta (https://youtu.be/cMMkBV9JyBY?t=38s).
Download:
WotLK (http://www.mediafire.com/file/q8428t8tb9e2848/Blood%20Mod%20%283.3.5a%29%20V3.rar) - Cata (http://www.mediafire.com/file/2p2a7bdldlzr8de/Blood%20Mod%20%28Cataclysm%29%20V3.rar)
(Old version (http://www.mediafire.com/file/qo63io7lrjg30q6/Blood%20Mod%20%283.3.5a%29%20V2.rar))
V2.0:
-Fixed crashes.
V3.0:
-Violence level is now always 2 and cannot be disabled or changed.
-Added purple blood (id 5).
IMPORTANT: to make it work correctly go to video settings and turn "projected textures" on. Also, set the "Particle Density" to High and set the Texture Filtering to High to avoid visual glitches (https://i.imgur.com/abTNCyV.jpg).
If you are using V2, make sure your violence level is set to 2. In-game, type:
/console violenceLevel 2
Known bugs:
-If you zoom in to first person view, you won't be able to see the blood splats from your character.
-If a character morphs into another model, all the blood splats from that character will disappear.
-The blood splats change color if your character changes color (curses, venom, etc.).
-The blood splats scale changes if the scale of your character changes.
-Blood effects do not show if you one-hit kill the target. It's hardcoded into the client and can't be changed as far as I know (happens with the default blood as well).
-It's not possible to use this mod in MoP since the game cleans all blood splats each time your character is hit or dies.
Note: The splats on the ground disappear after 45 seconds. You can change it by editing the particle lifespan in 010editor.
If you think there are too many blood splats to the point they overlap or affects the performance, just change the default particle emissionrate (12) to 7 or less with 010editor.
Blood color is set in CreatureModelData.dbc, column 6 (1 = red, 2 = green, 3 = black, 4 = blue, 5 = purple).