Rhys

Rhys is an NPC in the Obsidian Sanctuary, near the Lift Operator.

He will give the player access to the Dwarven Mines in exchange for 10 enchanted ingots of any 3 ores.

Dialogue
--- Before giving the ores ---

So you want to visit the Dwarven Mines?

You must prove yourself worthy of Heart of the Mountain...

You must bring me some valuable materials that peak my interest. I would like 3 of the following: 10x Enchanted Redstone, 10x Enchanted Iron, 10x Enchanted Coal, 10x Enchanted Emerald, 10x Enchanted Lapis Lazuli, 10x Enchanted Diamond, 10x Enchanted Gold

--- After giving the ores ---

Perhaps you are someone we can get along with after all.

I'll get your Heart of the Mountain. It's time for a visit!

Let's go together now. For future trips, remember the Lift Operator.

Trivia
Few hours after the Dwarven Mines update, misinformation spread that the NPC was unavailable to take the items and that admins locked the area to fix some bugs. This was debunked as he would take items when the player disabled your Skyblock addons mod.