All four of us strode into the room together, and I swivelled around as I heard the entrance we’d come through snap closed. I looked around for whatever threat was in this room that we were now locked in. It wasn’t the biggest of rooms, and I could see instantly that there was nobody in here except the four of us. Seabird pet slime, this teeny creature that she’d for some reason decided to name Raspberry, immediately became agitated, as though it could sense something that I couldn’t.

‘Why did the door shut, Ti?’ asked Seabird.

‘Not sure,’ I replied. ‘But the fact that there’s a visible exit over there strongly suggests that on the way over there, there will be some kind of trap. I’d suggest that we stick to the walls and make our way around, rather than crossing the fastest route.’ The others nodded, even Cal, who looked like he’d much rather just sprint across to the exit. We hugged the walls, going in single file with myself in the lead. Raspberry had crawled up onto Seabird’s back, his usual way of travelling around without legs.

I could hear a low level hissing noise, and couldn’t remember if I had heard it before the door shut, or only afterwards. I looked around for the source of the noise but couldn’t see anything. I could, however, smell something disgusting. The others started to cough, so they could obviously smell it too. The hissing increased in volume, and suddenly plumes of green fog were billowing up from the floor. They were giving off a smell so horrific that it was burning my nostrils.

‘Oh heck,’ I said, loud enough for everyone to hear me. ‘It’s a gas chamber, run for the exit, NOW.’

Callisto didn’t need telling twice. The moment I spoke he broke into a dead sprint, and his long legs carried him to the exit in record time. If he ever wanted to become famous, he’d be able to break records in racing, I was sure of it. To his credit, he did turn at the exit rather than continuing to run, and he shouted encouragements to the rest of us. I made sure that Seabird and Hawthorn were ahead of me, and even though we were all running at a gallop, I was beginning to feel a little wobbly. I was drawing in air as fast as I could, but I had a feeling that I was mostly breathing that vile green fog, rather than actual air. I almost tumbled as I didn’t watch where I was going and placed a hoof on a loose piece of rock. I was just a few steps from the exit when my vision started to go black. I cried out, and saw Callisto run back into danger to grab me.