You're implying that creationists have consistent arguments
. It varies from cretinist to creotard, of course, but it's not uncommon to see "checkmate proofs" of the impossibility of evolution because all mutations are detrimental, even fatal, to the organism. To this kind of closed and bolted mindset, mutations equal the typical 50s sci-fi monsters.

At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'