I've only been playing CTFs for 2 years (iCTF 2013), but I don't think I've seen FreeBSD there once. In my experience, it's 99% Linux, with some occasional Wind

I've only been playing CTFs for 2 years (iCTF 2013), but I don't think I've seen FreeBSD there once. In my experience, it's 99% Linux, with some occasional Windows and Android. Then there was last ruCTFe making a point of using some more obscure systems - Minix, OpenIndiana, etc.