Screenshots
History
Durandel, who recently came out of nowhere with a slick mod for Cataclysm called Onslaught, was assembling his final release and wanted a new seige cannon effect to fit his new mothership. I was glad to help, but soon remembered why I don't have many Cataclysm effects to my name. A variety of strange things seem to happen to the siege cannon without me or the EBG file telling them to happen. For example, the whole effect spins on the Z-axis, and there's nothing I can do about it. That stymied my plans for lightning crackling between the booms, but the effect I came up with is still pretty nice. The Onslaught mothership is huge, so I increased the size of the siege shot itself and threw on some extra bells and whistles, to prevent it from looking like a peashooter.
Instructions
Unzip osiege.zip into your Cataclysm directory. It will put files into the ETG directory that replace the original siege cannon. No further setup is required.