I tested Ham_BloodColor a long time ago, and I didn't have success. Maybe I was doing it wrong
Anyways, I don't think Ham_BloodColor will suffice for the red blood decals on the wall.
So, the solution is to record the red and yellow blood decal indexes and then write the yellow one after Ham_TraceAttack is called on the target player. If you want more details, I can write some real code.
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