Back in the first few years of the Exile, we had a lot of Magnatiles posts. Like this one for example. Recently, the Magnatiles have been in a plastic box with various wooden blocks and - although they have come out from time to time - they have been mostly neglected in the basement.
On the night of the party, the box with the 'tiles and the blocks was brought upstairs as potential young-child distractions. After the party, our youngest child (not quite the demographic we were thinking of) was inspired to give them a go and created this arrangement.
He did explain the various buildings to me, but I'm sorry to say that I've forgotten. I like them a lot though!