Walkthrough Guide:
1. Strengthen your stats with Charm Conduit
Adventure: Obtain a Charm Conduit and Charms from the Mountain
If this is your first time here, you need to buy the Charm Conduit.
With the Charm Conduit is in your inventory, you will be able to equip any charm to strengthen your stats.
The item is available to purchase in the Mountain - Charm Shoppe for 1,000 gold.
2. Equip Power Charm
Adventure: Obtain a Charm Conduit and Charms from the Mountain
Mountain - Charm Shoppe sells Power Charm for 200 gold each.
If you do not have this charm yet, you need to buy this or loot from any captured moues. 10-30 should be suffice to help you progress with the adventure here.
Make sure you equip the Power Charm.
3. Break boulder to get Chedd-Ore Cheese
Adventure: Break a Boulder
Keep hunting mouse here with the charm until you destroy the boulder.
4. Hunt with Chedd-Ore Cheese to get materials to craft Abominable Asiago Cheese
Adventure: Arm Chedd-Ore and Gather Supplies to Craft Abominable Asiago Cheese
5. Catch Abominable Snow Mouse with Abominable Asiago Cheese
Adventure: Catch an Abominable Snow Mouse and Find the Laboratory Map Piece
Now that you have the required cheese, you can start attracting and hopefully catching the boss mouse.
If you run out of the cheese, you can just repeat the process to crafting materials.
The Abominable Snow Mouse drops Laboratory Map Piece which is required to unlock Laboratory.
Do not forget to claim your Adventure Book reward bonus after catching the boss mouse.
If you have reached Master, you can continue your journey: Laboratory Guide
else, you can go to Calm Clearing. Here is the guide: Calm Clearing Guide