Mitzog

Mitzog was the leader of the Ethereals. Like the other members of his race, he was turned into a living cloud by their former servants, the Baggolts. After the First Doctor restored the Ethereals' original bodies, Mitzog offered him rulership of the planet, which he refused, instead offering to help them against the Baggolts. The Doctor, Mitzog and several Ethereals disguised themselves as Baggolts to enter Droog and break into the control centre. While Mitzog fought Nalog, the Doctor used a switch on the master panel to end the Baggolt rebellion. (DWAN: The Cloud Exiles)