While everyone was looking for things trying to escape from Prison Architect Introversion sneaked something in: the most awesomest Halloween treat of them all.

For those that don’t want it spoiled you’ve two days to find it. It’s going to be patched out on 1 November. Go!

But for those who want instructions of how to get it or a video of what it is, read on.

You’ll need a Prison Yard large enough for 30 prisoners of so. To be on the safe side, aim for something in the region of 10 x 10. Then you just need to populate that prison and sit back to see if the magic happens. If you want to be surprised by what it is then exit your browser now and definitely don’t click on the video below.

A thriller flash mob! How excellent is that? This excellent.

I do hope we’ve a lot more of these style of easter eggs being put into Prison Architect over the years.