Tuphal

Mentioned in Mort, this god has three eyes. "Tuphal's Eyes" is slang for getting three ones in the dice game crap, in a parody of Roundworld's Snake Eyes, which is the outcome of rolling the dice in a game of craps and getting only one pip on each die. The pair of pips resembles a pair of eyes, which is appended to the term 'snake' because of the long-standing association of this word with treachery and betrayal.