Break out the Emergency Warhammer!

I needed to keep my 6 year old son occupied while he waited for his swimming lesson to start yesterday, preferably in a manner that didn't involve him using my phone data or needing to bring a load of things on top of the swimming gear and lunch box I'd brought for him.

Our favourite shared activity right now is playing Warhammer 40,000 – or at least a version of it that he's comfortable with.