There are no rules for him. He's an old vintage model which was brought out at a time when the rules for chaos warriors and characters were a lot different! Unfortunately, there are no ranged weapons for chaos characters anymore, so you'll either have to use him as a proxy with different gear or come up with your own special rules for him (and you'll need opponents permission to use it).
If there's any other questions you have, please feel free to ask.
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