How to slay your dragon: Upon the dragon's back

Vex looks at the wyrm. He has just arrived and seeing how big it was took him by surprise. '"Okay I wasn't expecting this." He muttered grabbing his sword and letting it ignite in the silver of his flames. '"Welp now to get up on this things back." He said looking around for anything but he came up empty handed so he had to improvise. He ran at the wyrm. '"Come get me!" He shouted pointing his hand at the ground under himself and making a massive explosion of silver flame launching him up and onto the back of the crystal wyrm. '"I don't know how but it worked." He chuckled to himself before he started running down the back.of the wyrm dragging his sword along its back as dug in as he could push it to leave a slash along it's back as well as to prevent him from getting knocked off. It the started rolling in midair trying to make him fall. So vex started running against the spin dragging his sword along the width of the dragon. '"I can't believe this is working." He said to himself as he went switching the angle of his sword slightly to start going down in a spiral. Suddenly the dragon stopped spinning leading to Vex running off of the dragon and falling. Vex fell into a portal leading to him getting shot back into the air near his home and landing painfully on his face.