There was a brief period of time where the tower defence genre was a big deal and just about everyone was trying to get on board with it, right through to the biggest publishers. It’s easy to understand why – the games are relatively easy to develop, and it’s relatively easy to fill them with content. The genre has faded into the background as other things have come to the fore in the indie spaces – roguelikes, for example – but every so often something like Gnomes comes out to remind us...