I also had a secret challenge to put in unicorns (for reasons I'm not going to disclose at this time because it would take too long to explain). It was tricky (unicorns, space, and bicycles???), and probably not my best story (I needed a little more time and a lot more words to make it kick), but I had fun writing it. Hopefully you'll have fun reading it!
We waited with bated breath as Gwyllian approached, willing his power to hold the illusion for a little longer. He’d come the farthest and must be low on reserves.
The humans would build a road above our heartstone. How could they not feel the magic pulsing beneath their feet? Gwyllian wobbled – or the human riding a bike he was pretending to be did – and I shivered in fear. If he fell… No. He could make it another twenty feet.
Gwyllian made it under cover and dropped his illusion. His sides heaved. His mouth frothed. His withers twitched uncontrollably. His horn gleamed bright in the shade of the tunnel.
He drank from our bucket of water then spoke, “We haven’t much time. We mustn’t wait,” he said. We joined our horns together and connected to the heartstone.
Our ship – in geosynchronous orbit over the dark side of the moon – stood ready. The counsel needed to hear our report.