Urrr, the last time I checked (about a week ago) models can't be replaced. There are a few sites that do custom skins which can be imported but thats the best you can get. I've built one halflife model with working bone structure et al and I have to say, it's pretty hard work getting it just right. Animating a Shivan will be difficult because it would require it's own whole set of animations. I'm not so sure anything other than bipeds will work, it's extremely unlikely given the complexity of the AI. A vasudan shouldn't pose too much of a problem though.
I dunno though, us modders work fast so they might just have cracked it by now
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He strikes from the darkness. He is unseen, unheard, he is the snack ninja. Pray your refrigerator isn't next.
