It was supposed to coincide with the release of Starcraft 2, but with the schedule still undetermined (TBA), designer Jan Rükr gave in and released the Starcraft 2 Terran Marine Cannon, all fifty pages of it - pattern and instructions. There's also a gun stand that goes with it, it's on a previous post below.
Starcraft 2 Papercraft - Terran Marine Cannon [starcraft-2.cz]
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