Already have head canon.
The Wyvern raised it's head at the new smell in their domain, taking in deep breaths at the unfamiliar scent. The scaled beast got up and swam down the underground river, tacking the scent through the natural halls. To their slight dismay, a beam of light shown through the upper ceiling of their entryway.
How unpleasant, guess I'll need to patch this up... Wait... Something is up there.The wyvern climbs up the rocky walls to get a better look, just as a small hominid threw a rope down and began to descend like a spider on silk.
What manner of daring creature wishes to enter my home? This little thing? How curious... It is rather cute. I shall watch...

:o !
i adore this. thank you for sharing. i really enjoyed reading how you set up the world. <3

Gah, I made a mistake and didn't catch it. T,..,T *Tracking, not Tacking... Though I guess it works.

I do wish to see more of this Wyvern. ^,..,^ I only have one Wyvern of my own, so seeing such art that has nameless Wyverns like this helps me flesh him out, since he is - coincidentally - my oldest character.

Nice art! Had dragon and cave explorer idea for years now but not encountered artists willing yet to do it. Most not confident in there lighting art skills. This lovely art. Revived interest in idea I have put aside. Hope to see more art like this ^^

glad i could re-stoke the fire :3

would not mind exploring that idea with you. I like to think you can help put that art to life. This lovely piece inspiring me and all ^^

The human is rappelling down into that dark cave to witness the extraordinary climbing abilities of that wyvern. Think about it for a second; it's difficult for climbers to find purchase on a slick stone wall as straight as that one, let alone for a heavy wyvern who only has wing claws to leverage the weight of his upper body. So, quite the amazing feat :D He'll get congratulatory snoot rubs as he enters the guiness book of records for wyvern underground cave climbing :D

perhaps the human is the Guiness offical, come to hand over the plague to him. lol. im sure the wyvern will hang it in his cave with pride

I'd say the climber doesnt know and its going to have the surprise of his life! The wyvern doesnt seem hostile either but rather curious. In difficult terrain like this I doubt they'd act aggressively anyways. I like this picture a lot though, thanks for drawing it!

thank you! im happy you enjoy it

Oh this is just amazing Taz!

thank you Lev <3

Beautiful art my friend ;)