I realized I don’t have the latest WoC book and I was looking for the rules. I found THIS SET OF RULES ON GW SITE. Is that the latest rules? I’m just not sure. I know there is an errata for the WoC rules, but is this 7th Ed rules or maybe Storm of Chaos rules?
Yeah, those are the Storm of Chaos rules and that PDF dates from the brief period in 2008 between the release of Daemons of Chaos (which invalidated the old Hordes of Chaos book) and Warriors of Chaos, when WoC used a “get you by” PDF list that contained the Hellcannon (and referred players to the separate PDF that you linked). The current rules are quite a bit different.