Who Let the Gods Out? Book 4: Against All Gods

‘You have got to be kidding me.’ Elliot Hooper let out a deep sigh. Another way to die horribly. It must be Friday.
‘Nope,’ grinned Hypnos, Daemon of Sleep. ‘Welcome to the River Phlegethon! All you have to do is dive in and grab the Fire Stone! Simples!
But caution: this water is h-h-hot!’
‘Great,’ Elliot groaned, peering from the balcony edge into the blazing river of fire that raged between him and the final Chaos Stone. Even from the relative safety of Thanatos’s cliffside office in Tartarus, he could feel the wall of heat blasting off the flaming river metres below. He could just make out a blue glow shining through the flames on the riverbed. It was a huge sapphire: the Fire Stone. It was right there. Elliot reached a hand over the balustrade towards it. Perhaps the river itself wasn’t that hot . . .