The particle generator worked well for me, using metaballs to get a 'fluid' look. Unfortunately the final item is in the background of my image for that one... so barely visible unless I put a spotlight on it (still debating this). I used a plane with an image map in it for a splatter on a wall, and I haven't yet managed to get the 'blank' parts of the image map fully transparent, but I don't expect a problem with this (I didn't know about it until I did a render just before going to bed last night). I experimented with running the particle generator against a wall and seeing what clumped onto the wall, but I didn't get the effect I wanted and figured it would be too much hassle to adjust it until I could (I think I could with very small metaballs, shot in extremely high number, like a mist - but the poly count on that might not be worth the result). Instead the the image map was made in photoshop with some 'scatter' brushes and a wacom tablet... :) Attached is my project so far. For the blood on the ground, I just did mountain terrain maps with 'zero edge' and plateau filters.

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