My friend and I are currently trying to scientifically classify various mythological and fictional animals into our current taxonomic ranking system. How, we have reached a dead-lock on the supposed classification of a hypothetical Dragon.

My friend argues that Dragons should be classified as sub-order of Theropoda.

Meanwhile, I believe that they should be their own sub-clade of Dracohors; as they hold some very distinct evolutionary differences to Dinosauria, any input?