That's what I came here to say too.Bloodied.
Not just as an easy measure for "this creature is visibly wounded" (which I do anyway), but also for things like having monsters behave differently as they take damage, or indeed having them behave differently when the PCs take damage.
Even without bloodied, I'll make monsters that have things that trigger at half hit points, I just wish I could call it bloodied to save my word count.