Hi, I searched the forums and I couldn't find anything that described exactly what crouching does. After testing with some friends I discovered that it is impossible to score a headshot while crouching, as hits to the upper 2/3 of the hitbox count as torso. However, crouching negates the effect of light armor, so if a dretch bites a crouching human with larmor it will still do 48 dmg. The exception to this is dragoon pouncing. A fully charged goon pounce will still do 31 dmg to a crouching human with light armor. I also noticed that your hitbox does not change while crouching, so you can still chomp a human if you look in the same place that would score a headshot on a non-crouching human. If anyone has noticed anything else about crouching, or if the game code suggests something different, please let me know.
According to the above, you should always crouch in stage one, never crouch with a helmet, and never crouch when trying to fight a tyrant.
I also noticed that most dretches have a tendency to aim at the graphical head of a crouching human, which is roughly at leg level on a non-crouching human. So standing up when a dretch is about to bite you can minimize the damage you take. This can easily backfire if they aim at where your head should be like a smart dretch. Just thought I'd share that.
Note: I just realized that your hitbox has to change when you crouch because humans can jump on top of crouched humans to make human towers. So I'm not sure about what I said earlier. I opened up a server and set cg_drawBBox to 1, and when I crouched my hitbox didn't move. Its possible that the hitbox actually moved and I couldn't tell. However, I had my friend crouch and I was able to chomp them by aiming where their head would be if they weren't crouching, so I'm not sure. If anyone has definite information on this, I'd be interested to hear about it.
Thanks,
Riderrocker