Here is the full list of all 25 Unexplored 2: The Wayfarer's Legacy achievements.
Reach Haven after starting in the Garden of Yendor.
Boost a Scrying Stone to its maximum.
Use the Serpent Road to travel between two locations.
Find the Shadow Glade.
Reach the top of a mountain.
Defeat Valker.
Befriend another clan.
Form an alliance with 3 clans in a single world.
Enter the First Valley
Enter the First Valley through the secret tunnel.
Destroy the Staff of Yendor.
Destroy the Staff of Yendor on the first run in a world.
Lose all hope with a character.
Find all parts of the Raafi Legend.
Find all parts of the Empire Legend.
Give a map to the magentol mine to a clan.
Spot a Kelkos.
Use the Spirit Forge to unlock 5 sigil slots on an item.
Obtain the most expensive item through trade.
Wake the Flame Elemental.
Wake the Flow Elemental.
Wake the Form Elemental.
Wake the Root Elemental.
Wake the Sky Elemental.
Defeat the Double Dragon.