This is the hard-mode walkthrough for Fourbyfourian Quarryin'. If you are not comfortable with tricky puzzles or how chess pieces move, you may wish to see the normal-mode walkthrough or even the superbrief one that should be included in a ZIP file with these explanatory walkthroughs.

Here are some initial pointers as well as conventions for the walkthrough.

For each area, you need to stalemate the enemy king (corner him without a legal move, but he is not attacked) and then checkmate him (attack him so he has no legal moves). However, in cases where a stalemate puzzle would be identical or redundant, the game skips over it and gives you credit for puzzles you've already solved.

A key thing to note is that your king needs to do a lot of the work in every quest. It's more powerful than the bishop and knight, since it can potentially restrict three of his counterpart's squares, while the bishop and knight can only restrict two.

Your pieces are in capital letters. Your enemy's are in small letters. K = king, B = bishop, N = knight.

Note that there are multiple solutions, rotating the board or flipping them. I went with the upper left corner for the sake of consistency, but everything should work.

Also note that this walkthrough uses abbreviations a lot, since the game allows them. The game parser will be able to disambiguate most of the time. It favors reserved pieces over placed ones over irrelevant ones and allies over enemies and traitors. Therefore, you may just find some shortcuts easier: n is knight, b is bishop, k is king. E is enemy and f is friendly, but you can also use the colors. Yellow and purple are randomly chosen for the first for quests--there are two of each--but enemies are always grey. So you can say yb or by or y b or b y for, say the yellow bishop, or pn or np or fn or nf for the purple knight. For the kings, no abbreviation is needed, since the enemy king must be placed last.

You can even risk one-letter abbreviations to save keystrokes. FQ tries to guess what you mean. For instance, c b or p b both place your bishop, as it takes priority over the enemy bishop, and when you have two bishops, the game just picks randomly. You can even use just c or p to call or place the final piece (always the Fourbyfourian King) or second-final piece (whoever's not the Fourbyfourian King).

Fourbyfourian Quarryin' is divided into seven quest zones: four where you have an enemy ally and three where you have two allies. The Fourbyfourias are arranged so there are always bishop allies in each southern conquest and knight allies in each eastern conquest.

+-----------+---+
|           | N |
|           |4b4|
|           |   |
|           +---+
|           | NE|
|           |4b4|
|           |   |
|           +---+
|           | E |
|           |4b4|
|           |   |
+---+---+---+---+
| W | SW| S | SE|
|4b4|4b4|4b4|4b4|
|   |   |   |   |
+---+---+---+---+

All of these solutions will work to solve normal mode. However, if you wish to solve normal mode, you may wish to see the normal mode walkthrough first, because its solutions are simpler and more intuitive.

First, the stalemates. Note you only have to perform each stalemate below once, since your allies in the north/northeast and west/southwest are equivalent. Once you stalemate, you'll need to perform a checkmate next.

======================================== WEST/SOUTHWEST STALEMATES (king and knight vs. king):

The idea here is that you need to trap the enemy king without attacking him. If he is in the corner, your minor piece can take one square, and your king can take the other two.

This is not the only solution. There are rotations and mirrors, and the knight has two squares, and your king can be in one of two squares as well. But this is the general idea.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | |N| | | 3
  +-+-+-+-+-+
2 | | |K| | | 2
  +-+-+-+-+-+
1 |k| | | | | 1
  +-+-+-+-+-+
   a b c d e

place n/s/place k/a1/place k

======================================== NORTH/NORTHEAST STALEMATES (king and bishop vs. king):

Similarly to the king-and-knight stalemate, the bishop can guard the square your king can't.

However, in hard mode, this doesn't work! The enemy king doesn't want to be in a corner. That's the in-game reason. The fourth-wall reason is, it's hard mode, so you may be forced to think of alternate solutions. You need to guard five squares! Your king can take three, at most. Your bishop, two.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | |K| | | 3
  +-+-+-+-+-+
2 | | |B| | | 2
  +-+-+-+-+-+
1 | | |k| | | 1
  +-+-+-+-+-+
   a b c d e

place k/s/place b/s/place k

You're now given a pass on stalemates for the two areas you didn't visit, because you have identical allies in, say, the north and northeast, and repetition can be boring. So, on to the checkmates. Note that you need to make sure the traitorous piece is not attacking your king in your solution. There are no potential surprises with the knights, so let's tackle them first.

You may note that the king in the corner only has three squares to move to. Elsewhere he has at least five. So you want to put him there and then leave no escape squares. Your king can guard two squares, but your knight can't guard any if it is giving check. That means the bishop has to block a square. If the bishop is next to the king, that eliminates one square where the knight gives check. With the knight placed, there's only one square for your king that adequately blocks the opponent's king.

Now ahead are checkmates that would never happen in practical play unless a player wanted to lose deliberately. We present the knight mates first, then the bishop mates, which are a bit trickier.

======================================== WEST (knight vs. knight):

You can use process of elimination for this. The king in the corner has three potential flight squares. Your king can guard two. The knight must give check and can't guard any. So the enemy knight has to block one square. But when it does, it makes one of the squares for your king impossible. Since that square is a knight's move away, you need your knight on the other square.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | |N| | | | 3
  +-+-+-+-+-+
2 |n| |K| | | 2
  +-+-+-+-+-+
1 |k| | | | | 1
  +-+-+-+-+-+
   a b c d e

s/place k/nw/place n/sw/place n/s/place k

======================================== SOUTHWEST (knight vs. bishop):

You can again use process of elimination for this, though in this case, the bishop restricts where you can place the knight.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | | | | | 3
  +-+-+-+-+-+
2 |b| |N| | | 2
  +-+-+-+-+-+
1 |k| |K| | | 1
  +-+-+-+-+-+
   a b c d e

s/place n/s/place k/a2/place b/s/place k

======================================== NORTH (bishop vs. bishop):

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | |B| | | 3
  +-+-+-+-+-+
2 |b| |K| | | 2
  +-+-+-+-+-+
1 |k| | | | | 1
  +-+-+-+-+-+
   a b c d e

As before, you need to give check, and while the bishop can guard one flight square, it leaves two squares your king can't guard both of. So you still need help from the opposing bishop. Here, your king has a choice of two squares, since the bishop can't check it, and your bishop has a choice of four squares to give mate.

Note that if there is an ambiguity, you will place your allies first, so your yellow or purple bishop drops with "place b," after which you then place the grey bishop with "place b." This saves a few keystrokes.

place b/s/place k/a2/place b/s/place k

======================================== NORTHEAST (bishop vs. knight):

First, a detour to something that looks good but doesn't quite work:

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | |B| | 4
  +-+-+-+-+-+
3 | | | | | | 3
  +-+-+-+-+-+
2 |n| |K| | | 2
  +-+-+-+-+-+
1 |k| | | | | 1
  +-+-+-+-+-+
   a b c d e

Here, the knight can block. Similarly, if the bishop is in the center, the knight can just take it. The bishop, despite being a ranged piece, needs to be kitty-corner from the enemy king.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | | | | | 3
  +-+-+-+-+-+
2 |n|B|K| | | 2
  +-+-+-+-+-+
1 |k| | | | | 1
  +-+-+-+-+-+
   a b c d e

s/place k/w/place b/w/place n/s/place k.

Now you need to checkmate with two pieces. I'll put in a spoiler of how to do things at the end, but a semi-spoiler is: the three solutions are all very similar!

But now things may get a bit trickier. You have two full allies who can attack the enemy king, but he is too smart to be suckered into the corner. He's heard rumors. And checkmate won't work at first! Again, you have to sucker him by trapping him with stalemate--where he has no legal moves, and he doesn't have any subjects who can move legally. There is also one special case where a solution you might expect doesn't work.

There are plenty of alternate solutions not counting rotations and shifting pieces one square over. They are included in a PDF file.

As for general logic in hard mode: if the enemy king is on the side, that's five escape squares you must stake out, including the check square. Each knight or bishop can stake out at most six squares in the 3x2 rectangle you need to cover. That leaves at least two squares your king must cover

======================================== SOUTH (two knights):
First, the stalemate. Here is one I found particularly entertaining:

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | |K| | | 3
  +-+-+-+-+-+
2 | |N| |N| | 2
  +-+-+-+-+-+
1 | | |k| | | 1
  +-+-+-+-+-+
   a b c d e

It's far from the only one, but I think the diamond arrangement of the pieces is visually appealing.

place k/sw/place n/d2/place n/sw/place k

Now for the checkmate:

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | |N| | |N| 3
  +-+-+-+-+-+
2 |K| | | | | 2
  +-+-+-+-+-+
1 | | |k| | | 1
  +-+-+-+-+-+
   a b c d e

w/place n/sw/place k/e3/place n/c1/place k

This is the only solution--apart from moving your king to a1, which is only trivially different.

======================================== EAST (two bishops):

Since again you can't force the enemy king into the corner, you need to find a way to take care of it when it is on the edge. Here's where it gets a bit complex. The enemy king is claustrophobic enough that having a bishop in front of him and a king behind the bishop makes him suspicious. But diagonal? That's okay. He can see your king from there.

I included two of my favorite stalemates. The first could happen in a real game. The player with the bishops wants to push the lone king against the side of the board, but they need to make a waiting move with their bishop, not come in with their king, to push the lone king into the corner. The first example shows what happens if the player with the bishops doesn't know how to roll the king up. It doubles as a solution to this game.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | |B|B| | | 3
  +-+-+-+-+-+
2 | | | | | | 2
  +-+-+-+-+-+
1 |K| |k| | | 1
  +-+-+-+-+-+
   a b c d e

place b/w/place b/a1/place k/c1/place k

Below is an alternate stalemate. Note the bishops are on same-colored squares, which never happens unless you deliberately underpromote one, which is very rare indeed. But it's still a tidy, compact solution.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | |B|K|B| | 3
  +-+-+-+-+-+
2 | | | | | | 2
  +-+-+-+-+-+
1 | | |k| | | 1
  +-+-+-+-+-+
   a b c d e

place k/w/place b/d3/place b/c1/place k

Also, the game deliberately pokes you so you can't have a similar position for 2B as for 2N. Note you can just swap the knights for bishops above and get a checkmate. But this doesn't work: either it's done before, or doing it now might spoil the surprise for later when it's necessary.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 |K| | |B| | 3
  +-+-+-+-+-+
2 | |B| | | | 2
  +-+-+-+-+-+
1 | |k| | | | 1
  +-+-+-+-+-+
   a b c d e

e/place b/a3/place k/se/place b/s/place k

The following legal (if unusual in practical play) checkmates are thus rejected:

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | |K| | | 3
  +-+-+-+-+-+
2 | | |B|B| | 2
  +-+-+-+-+-+
1 | | |k| | | 1
  +-+-+-+-+-+
   a b c d e

The below is too much like the two-knights' mate, so it was a judgement call on my part to discourage it. I wanted to have you find solutions where you didn't drop the minor pieces on the same squares each time.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 |B| | |B| | 3
  +-+-+-+-+-+
2 | | | | | | 2
  +-+-+-+-+-+
1 | | |k| |K| 1
  +-+-+-+-+-+
   a b c d e

======================================== SOUTHEAST (bishop and knight):

Stalemate has many options here. The simplest is to make a king-bishop-king battery, but one I like is below. It is not the most convenient or efficient.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 |N| | | | | 3
  +-+-+-+-+-+
2 | | | | | | 2
  +-+-+-+-+-+
1 |B| |k| |K| 1
  +-+-+-+-+-+
   a b c d e

a3/place n/a1/place b/e1/place k/c1/place k

There are two ways to checkmate, since you are not restricted by the claustrophobia with the two bishops.

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | |K|N| |B| 3
  +-+-+-+-+-+
2 | | | | | | 2
  +-+-+-+-+-+
1 | | |k| | | 1
  +-+-+-+-+-+
   a b c d e

place n/w/e3/place b/c1/place k

   a b c d e
  +-+-+-+-+-+
5 | | | | | | 5
  +-+-+-+-+-+
4 | | | | | | 4
  +-+-+-+-+-+
3 | | |K|N| | 3
  +-+-+-+-+-+
2 | | |B| | | 2
  +-+-+-+-+-+
1 | | |k| | | 1
  +-+-+-+-+-+
   a b c d e

place k/e/place n/sw/place b/s/place k

Once you've done this, congratulations! You have won on hard mode!