Guido da Montefeltro

When the two-horned flame goes back into its smoke, at the foot of the climb out another one comes behind it, with a single horn, as in the canto. Its words first come out in the language of the fire, closed and bellowing like the brass bull of Sicily, and only then find the tip: it is the most muffled voice in the game, and it starts calling only once Ulysses has fallen silent. It stands on the outer half of the floor, off the ramp you climb, and it burns whoever touches it like every other flame, but not whoever speaks to it from a step away.

He is the only soul in the game to whom the truth buys nothing. He speaks only because he believes nobody will ever climb back up from this depth to repeat it: tell him you are going back and the flame stands upright and still and says nothing more. Lie, and he tells you who he was, how the great priest sent him back to his first sins and how a black cherub took him with a point of logic; and then one true thing about the next ditch, from a man who knew every covert way: the devil with the sword strikes in time and you can hear it, arrows bounce off him, a sacred blow holds his arm up for two beats. His name goes into the book as taken by lying. Walk past in silence and the flame leaves in pain, writhing its horn, and goes out.