Dretches don't block dragoons/tyrants.

[ppetr]

Walk under them.

[ppetr]

I tried a simple thing: Making dretches smaller than the maximum step height:

diff --git a/assets/configs/classes/level0.cfg b/assets/configs/classes/level0.cfg
index 1497918..7a9718b 100644
--- a/assets/configs/classes/level0.cfg
+++ b/assets/configs/classes/level0.cfg
@@ -1,15 +1,15 @@
-name              "Dretch"
+Name              "Dretch"
 model             level0
-modelScale        1.2
+modelScale        1
 skin              default
 shadowScale       0.5
 hud               alien_general_hud

-mins              -15 -15 -15
-maxs              15 15 15
-crouchMaxs        15 15 15
-deadMins          -15 -15 -15
-deadMaxs          15 15 15
+mins              -15 -15 -7.5
+maxs              15 15 7.5
+crouchMaxs        15 15 7.5
+deadMins          -15 -15 -7.5
+deadMaxs          15 15 7.5
 zOffset           -5.0

 viewheight        0

Works indeed - they don't block any more, even not humans. Anyone, even trampling rant, just walks over them. (Now they could actually help rants to fly a bit and then crush.) The problem is that the bounding box is not a cube any more (and making a dretch 2x smaller in all dimensions makes it impossible to hit) and bounding boxes don't rotate. So a wall-walking dretch has an incorrect bounding box, which makes it harder to hit, can fit into too small holes etc. But it's a good start, maybe modifying PM_StepSlideMove (which checks steps) will work.

[ppetr]

Maybe humans walking over dretches (or at least battle suits) could damage them a bit. It makes sense that a rushing team of battle suits crushes a dretch running in their way.

[ppetr]

Smaller dretches were to hard to hit, it shifted balance significantly. I had to revert it. Another option to try would be to make big aliens non-coliding for dretches (similraly to corpses, which are non-coliding for everyone).