Shadow Dragon
"Then let's finish exploring so we may exit quickly when we're ready.", the dragon says, stopping beside the kobold. "Perhaps you should ride me so we can search at a faster pace?"
SpoilerWill begin moving at 90ft movement speed when/if the kobold hops on and continue as before. He'll stop if he see's any kind of door, of if the kobold urges him to stop.
Hopefully, he's making spot checks too.
Spot - (1d20+15)[18]
Listen - (1d20+15)[28]