Boom

When they came up to the cave, they were surprised to find…

Narrow.

This cave was very narrow.

Though it was still big enough for a wyvern to fit, there was no doubt that it would be a very tight fit.

So when the princes saw this, they all immediately questioned the ones that they had sent to follow Duke Zwein.

"It's this cave."

That was what all of them said.

They had all seen Duke Zwein enter this cave with the wyvern that he was riding, so they couldn't be mistaken about this. Though they had also felt suspicious of this when they saw this for the first time.

This was something that they tried to convey to the princes, but the princes just ignored them and insisted on continuing into the cave.

Since the cave was so narrow, that meant that not everyone was able to go in at the same time. So they had to only allow their most elite followers to go in first.