Is there any way you guys know how to do this? Basically I want to replace the model, but have them act the same.
Wait roughly six months.
Zing
Other than waiting for BM though, I doubt it.
To put it in easy terms,
1] Decompile
2] Use decompiled rig to model a creature
3] Make sure the model uses the rig correctly so you can reuse the animations
4] Texturize
5] Write QC
6] Compile
https://developer.valvesoftware.com/ <---- search here for more detailed steps
I give you a 60% chance you actually search, another 30% chance you start working, and a 90% chance of giving up.
Prove me wrong.
What software then should I use.
Hammer
ur doin it rong
Hammer is the map editor. And are you f***ing kidding? The two game engines are obviously different, and I really don’t see why you would think it’s easy (it’s not).
I didnt think it would be easy.
It’s going to be much, much harder than you think. Plus goldsrc doesn’t support bump/normal mapping or specular mapping, and you’ll probably end up having to reduce the polies so much that the end result looks about the same as what you started off with.
STEP IN TIME!!
Just to add, you would have to do it yourself because it would be illegal to share content from a retail game, unless the devloper allows it (ie: S.T.A.L.K.E.R).
Didn’t someone get the poison zombie into goldsrc?
Yeah… It was in apost asking for real time zombie transformations in the mod. Someone said it wasn’t possibble, another guy said it was, then there was this huge debate. Somewhere along the line someone posted a video to a Hl1 mod showing a transformation. The mod had a bunch of other crap in it ripped from other games INCLUDING Hl2.
Someone got ALL of the zombies AND the Vort into goldsrc.
It’s a mod and it’s out there somewhere, but for the life of me, I can’t remember the name of it.
The WIP Mod War of Xen has Fast and posion zombies in it, and a scientist that transforms into a monster.
https://www.youtube.com/watch?v=LgtowvPauG8
Yeah! There you go…
Only the transforming ones are custom…the rest is ripped 
I know nothing about doing such things, but wouldn’t the easiest way (excluding waiting < or = 6 months) be to somehow bring HL2 vorts into HL: S? At least it seems like it would be easier to transfer a vort from one source game to another rather than to bring one from a source game to a gldsrc game…
gcfscape -> copy -> paste -> doubleclick