Arad was about to kill the white dragon. He had no reason to let the old lizard live. If he lets him live, he might attack the city again once Arad leaves, so he can't take any risks.
Arad disappeared from the dragon's vision. He had stopped messing around, and it's time to put an end to those. He has people waiting for him in the city, and he would rather not leave them alone.
Arad grabbed the white dragon by the tail and pulled him in. The dragon struggled, trying to escape and run away, but Arad's grip wasn't something he could escape from.
Arad screamed as he swung the dragon around in circles, using him as a club to hammer and kill the trolls. The poor creatures couldn't believe their eyes and didn't even bother to run. If their enemy can toy with a dragon like that, then they are as good as dead.
From the sheer force Arad used, the white dragon's tail ripped apart and was torn, letting the dragon's body fly away and smack into the mountains with a deafening shockwave.
