Sixth Drax

From Tardis Wiki, the free Doctor Who reference

The Sixth Drax was one of Inspector McCormick's "half a dozen best men".

As such, he was present when McCormick was called to arrest the third, fifth, ninth and twelfth incarnations of Drax. They later all ran away in McCormick's TARDIS. (AUDIO: The Trouble with Drax)

This incarnation was the one which the quantum assassin he killed. (AUDIO: Here Lies Drax)