The House of Hades (Heroes of Olympus Book 4)

that’s enough. Otherwise … things could get messy.’
    Hazel pursed her lips. ‘Let’s get going,’ she suggested.
    Halfway across the piazza, everything went wrong, but it had nothing to do with ghosts.
    They were skirting the well in the middle of the square, trying to give the cow monsters some distance, when Hazel stumbled on a loose piece of cobblestone. Frank caught her. Six or seven of the big grey beasts turned to look at them. Frank glimpsed a glowing green eye under one’s mane, and instantly he was hit with a wave of nausea, the way he felt when he ate too much cheese or ice cream.
    The creatures made deep throbbing sounds in their throats like angry foghorns.
    ‘Nice cows,’ Frank murmured. He put himself between his friends and the monsters. ‘Guys, I’m thinking we should back out of here slowly.’
    ‘I’m such a klutz,’ Hazel whispered. ‘Sorry.’
    ‘It’s not your fault,’ Nico said. ‘Look at your feet.’
    Frank glanced down and caught his breath.
    Under their shoes, the paving stones were moving – spiky plant tendrils were pushing up from the cracks.
    Nico stepped back. The roots snaked out in his direction, trying to follow. The tendrils got thicker, exuding a steamy green vapour that smelled of boiled cabbage.
    ‘These roots seem to like demigods,’ Frank noted.
    Hazel’s hand drifted to her sword hilt. ‘And the cow creatures like the roots.’
    The entire herd was now looking their direction, making foghorn growls and stamping their hooves. Frank understood animal behaviour well enough to get the message:
You are standing on our food. That makes you enemies.
    Frank tried to think. There were too many monsters to fight. Something about their eyes hidden under those shaggy manes … Frank had got sick from the barest glimpse. He had a bad feeling that if those monsters made direct eye contact, he might get a lot worse than nauseous.
    ‘Don’t meet their eyes,’ Frank warned. ‘I’ll distract them. You two back up slowly towards that black house.’
    The creatures tensed, ready to attack.
    ‘Never mind,’ Frank said. ‘Run!’
    As it turned out, Frank could
not
turn into a rhino, and he lost valuable time trying.
    Nico and Hazel bolted for the side street. Frank stepped in front of the monsters, hoping to keep their attention. He yelled at the top of his lungs, imagining himself as a fearsome rhinoceros, but with Ares and Mars screaming in his head he couldn’t concentrate. He remained regular-old Frank.
    Two of the cow monsters peeled off from the herd to chase Nico and Hazel.
    ‘No!’ Frank yelled after them. ‘Me! I’m the rhino!’
    The rest of the herd surrounded Frank. They growled, emerald-green gas billowing from their nostrils. Frank stepped back to avoid the stuff, but the stench nearly knocked him over.
    Okay, so not a rhino. Something else. Frank knew he had only seconds before the monsters trampled or poisoned him, but he couldn’t think. He couldn’t hold the image of any animal long enough to change form.
    Then he glanced up at one of the town-house balconies and saw a stone carving – the symbol of Venice.
    The next instant, Frank was a full-grown lion. He roared in challenge, then sprang from the middle of the monster herd and landed eight metres away, on top of the old stone well.
    The monsters growled in reply. Three of them sprang at once, but Frank was ready. His lion reflexes were built for speed in combat.
    He slashed the first two monsters into dust with his claws, then sank his fangs into the third one’s throat and tossed it aside.
    There were seven left, plus the two chasing his friends. Not great odds, but Frank had to keep the bulk of herd focused on him. He roared at the monsters, and they edged away.
    They outnumbered him, yes. But Frank was a top-of-the-chain predator. The herd monsters knew it. They had also just watched him send three of their friends to Tartarus.
    He pressed his advantage and leaped off the well, still baring his fangs. The herd backed off.
    If he could just manoeuvre around them, then turn and run after his friends …
    He was doing all right, until he took his first backwards step towards the arch. One of cows, either the bravest or the stupidest, took that as a sign of weakness. It charged and blasted Frank in the face with green gas.
    He slashed the monster to dust, but the damage was already done. He forced himself not to breathe. Regardless, he could feel the fur burning off his snout. His