Saul (The Tests of Trefus)

Saul was one of the fair-haired people on an unnamed planet, and hence a slave of the black-haired people. He was their strongest swimmer, and was willing to attempt the first of the tests of Trefus, which involved swimming across a crocodile-infested lake. The Second Doctor helped him pass the test by using explosives to temporarily stun the crocodiles. (COMIC: The Tests of Trefus)