Ixa, also known as the Great Ixa, was the leader of the people of Ixon. When Grig, the First Doctor, John and Gillian came to Ixon looking for the cure for the plague afflicting the Therovians, Ixa's men captured them and brought them to him. Learning what they had come for, he allowed them to collect the moss, but when they returned he announced that the Therovians should pay for it with all their wealth. The Doctor used his matches to set fire to the room and his party escaped to their ship. (COMIC: The Therovian Quest)