12 ground units is right, you’ve got everything unlocked. The empty space is a side effect of the Armory layout – before Campaign 2 existed there was just the one page of ten weapons. When we added the two new Campaign 2 weapons we had to include the new page as we couldn’t squeeze any extra slots in on the first page.
Let us know how you get on with Psycho Campaign 2 – there’s been some discussion of tactics for the later levels so it’d be cool to see how you approach them 🙂
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