Main Walkthrough

Guide is a work in progress.

Once you get far enough into Yog-Sothoth's Yard Little Leaf will help unlock a new resource-gathering minigame for your hotel: Mine Excavation. Located out in the Yard, Mine Excavation is a night-only activity that allows you to dig deep into a mine shaft and extract valuable minerals.

This guide will teach you the basics of Excavation in Yog-Sothoth's Yard. It's a relatively simple task, and worth the effort - though first you need to learn how to play one of the older games to appear on a PC: Minesweeper.

Excavation Basics

The Excavation game plays identically to Minesweeper. The rules are pretty easy. When a match begins you'll be faced with a field of obscured tiles. Click on a tile to reveal what's hidden underneath. Under each tile you'll find one of three things:

  • A blank tile
  • A number
  • A patch of Pollution
If you find a blank tile you're in the clear. If you find a number you're also in the clear, but this is also a sign that there's a Pollution patch right next to the tile you revealed. The number indicates how many Pollution patches are directly adjacent to the tile. If you hit a Pollution patch, well... Game Over. Your goal is to reveal as many blank or numbered tiles as you can without hitting any Pollution. 

The trick to Excavation is to pay close attention to the numbers, and try to hedge your bets when clicking on a tile. The numbers indicate how many Pollution patches are adjacent to the numbered tile. This includes diagonally-adjacent tiles, so if you hit a numbered tile the Pollution patch could be up, up-right, right, down-right, down, down-left, left, or up-left from the numbered tile. (This number is of course whittled down by any clear tiles you've already revealed.)

Sound simple? It generally is, though you need to use a bit of problem-solving to survive a round of Excavation.Take a look in the top-left corner of the image above as an example. There are three obscured tiles left, and they're surrounded by several 1s, 2s, and a 3. There are only three covered tiles adjacent to the 3, so they must all be Pollution tiles. If that was a 1 or a 2, however, it's possible that one of those three tiles could be clear. You need to take all of the nearby numbers into account before you click any tiles.

(That said, the first click is always a blind click, and there's a chance you might hit a Pollution tile right off the bat. Not much you can do about that.)

Whether or not you successfully avoid all of the Pollution tiles you'll receive some items once the game is over. You'll also dig deeper into your current layer of the mine, and once you dig far enough you'll reach a new layer. Deeper layers yield better items.

There are a few more things to keep in mind as you Excavate:

  • Again, you can only perform an Excavation at night. This limits how much digging you can do, so don't hinge your entire economy on Excavating.
  • You can Upgrade your excavation vehicle to improve its performance. This increases the size of the Excavation area, allowing you to collect more items - but it also adds more Pollution to the field. (You should still Upgrade when possible, just keep in mind that each game will likely take longer.) It costs 1 AP, as well as increasing amounts of other resources, to Upgrade your vehicle. You can upgrade you vehicle to Level 15 at the maximum.
  • If you click on a cleared area while Excavating every adjacent tile that is also clear will be cleared as well. This effect stops once you hit any numbered tiles.
  • If you click any of the numbers the tiles adjacent to it will disappear for a second. This is not a clue that there are no Pollution dumps in these squares! It's just meant to show you which tiles might contain Pollution.
  • Every ten layers you'll receive some bonus items. They appear as a treasure chest on the right side of the green progress bar that keeps track of how deep you've gone. You need to click the treasure chest to claim the items.
  • If you right-click on a covered tile you'll place a small flag on the space. You can use this to remind yourself not to click on tiles where you know you'll find Pollution. Right-clicking again on the flag will make it disappear.
  • The lowest Excavation Layer you can reach is 50. You can keep Excavating after this, but you won't get any deeper.
  • If you want to practice without using AP, I recommend just playing some Minesweeper. It's fun! (If frustrating!)
You'll receive the Underground Explorer Achievement for reaching the fifth layer of the mine.

Excavation Items

Whenever you go Excavating you'll receive items. The number of items you receive correlates to the amount of spaces you cleared without hitting any Pollution. In other words, the longer you survived the trek down the mine, the greater the reward. As you get deeper you'll unearth better items, as well.

This is a list of the items you can pull out of the mine. You'll need to dig deep to get some of these. (I'll be adding more items to this list as I go.)

  • Alexandrite
  • Amethyst
  • Ambergris
  • Ancient Stone
  • Bipedal Lizard
  • Black Blood
  • Black Gold
  • Blue Crystal
  • Cinnabar
  • Copper
  • Cursed Stone
  • Dragon Claw Crystal
  • Fossilized Sea Creatures
  • Hosta Flax
  • Impure Gold
  • Iron
  • Lead
  • Mud Frog
  • Silver
  • Stone
  • Sulfur
  • The Prying Eye
  • Tin
  • White Crystal

Main Walkthrough