One of my favourite human beings, colleagues and collaborators - Dr Paul Geil - also came up with one of my favourite paper titles of all time. The work using DRAGONS focusses on the structure of the Epoch of Reionisation. In the first billion years after the Big Bang growing galaxies shone with ionising UV light, lighting up the Universe itself. This light ionised the hydrogen gas lying around the galaxies, creating cavities or bubbles in the intergalactic medium. the exact structure of the bubbles, how many of a given size and their rate of growth, is intimately tied to the nature of dark matter and the physics of galaxy formation. Paul predicted how new telescopes like the Square Kilometre Array can explore these bubbles, and exactly how awesome they will be at constraining all sorts of physics. A huge piece of work that will be years in the testing, so forward looking is its predictions.