I think it would look less like smoke if it was separated, instead of having 4 spots in one image have 1 spot per decal and maybe have some differences between them and adding droplets.
You should be careful though creating more realistic blood and how you use it as this is where a moderation issue could arise.
Hm… Alright. I may just keep it like this so that if I get moderated I can call it red smoke. It is a UI background, so that should work.