From Chris Hannah:

Using my minimal theme as a base, I’ve now created another theme. This time it’s a bit louder, probably a tad more niche, but definitely has character.

It’s called Fortis, which is Latin for “strong”. As this is definitely a strong theme, that may not suit most people’s tastes.

In many ways it’s similar to the Pure theme, with the layout being practically the same. But as was the purpose of that theme, it served as a good base for more custom designs.