Tips and Tricks when playing Picross

Note: Because of the simplicity of this guide, there won't be a table of
contents. Everything I need to write for this can be placed in one section.
Additionally, this guide is NOT going to hand you the answers to the puzzles.
Games like this just aren't as fun if you already know how to solve it.


Hello everyone, sonikku here with another game guide. This is a relatively
simple guide which will detail some more advanced play tips on how to play
Picross, as the how to play sections don't teach you what to look for in the
puzzles. Hopefully with my guidance, you'll be able to complete the puzzles
without any hand holding, especially if you intend to do the mode that doesn't
alert you to your errors. This is also another general guide that is intended
for all of the Picross games on Vizzed, not just Picross 2.


First off, let's start off with the basics. Picross is a fill in the blank
logic style puzzle game where the answer forms a neat little picture. You're
given a (usually) square grid with a bunch of numbers surrounding it on two
sides. These numbers represent the squares you need to fill in on the game
board. A 5 will ask you to simply fill in 5 squares in that row or column in a
row, while a 3 1 will ask you to fill in 3 squares, followed by 1 square, with
a separation of AT LEAST 1 space. If you're successful, you make a picture.
In normal rules (Mario's Picross in this game), mistakes will dock you time;
2 minute penalty for your first mistake, 4 minute penalty for your second
mistake, and 8 minute penalty for every mistake after the second. In puzzles
with multiple sections, these penalties WILL carry over through the entire
puzzle. In free rules (Wario's Picross in this game), you are not charged for
mistakes, but the game does not tell you when you've made one. Pay attention
to what you've filled in if you think you've completed a puzzle but the game
doesn't tell you you've succeeded, and make sure ALL of the numbers add up.
In Mario's Picross 2 and onward (including the SNES incarnations), you can
mark off numbers you think are completed by highlighting the number and
marking it, to help you keep track of your progress.

Now for more advanced techniques. For these, I will be assuming a standard
15x15 grid is in use, as this is the most common type of puzzle in my
experience. In examples, X is confirm empty, O is confirm fill, - is unknown.
Additionally, I will always be using rows (easier to show examples with), but
anything you can do for a row, you can do for a column. They are not mutually
exclusive.

Tip 1: Find your 15s and your 0s. These can immediately be filled in, as all
separations (in the case of 15s) are exactly 1 space apart, and the all 0s
means that row is empty, which can significantly reduce the time it takes to
complete the puzzle. (If the 0 is on an edge, reduce the 15 by the number of
empty rows along that edge; if there are 3 empty rows at the top of the
puzzle, your columns only need 12 to fill in.) Let us take the following
example:

5 5 3 ---------------

To find the value of this row, we add up the three numbers presented to us.
5+5+3=13. To this value, we add the number of numbers in that row, minus 1. We
have 3 numbers, so 13+3-1=15. Because this row is 15, we can fill it in with
no problems.

5 5 3 OOOOOXOOOOOXOOO

As another example, let's say we don't have a 15 in our row, but we know from
columns that some spaces will be empty. Let's take a look at the following:

6 4 1 X-------------X

While not displayed in the example, the left and right edge columns in this
example happened to be 0, so we know the edges contain nothing. This reduces
our 15 check to 13. So now we do our math as before. 6+4+1=11. 11+3-1=13. We
can go ahead and fill this row in.

6 4 1 XOOOOOOXOOOOXOX

Tip 2: Fill in common ground. Common ground is for any rows that have a value
smaller than 15, but the difference between its value and 15 is smaller than
the numbers given for that row. This seems confusing at first, so let me give
an example.

6 4 1 ---------------

It's the same thing we did above, except this time we don't have any 0 columns
to help us out. This row has a value of 13, which is not 15. If the numbers do
not match up, subtract the value of the row from the target value. 15-13=2.
Next, we check our numbers in the row for any numbers that have a value
greater than 2. As it so happens, we have two numbers that are greater than 2:
6 and 4. So, counting from the left edge (top edge for columns) and starting
with the left (top) number, you count spaces until you get larger than the
difference value shown above and fill in. Once you hit the target value, you
skip a space and start counting for the next number, and repeat until filled
in, like so:

6 4 1 --OOOO---OO----

No matter what the answer winds up being for that row, the spaces that I've
filled in will ALWAYS be correct. To find the rest, you'll need to do some
work with the columns and slowly fill it in as you go.

We can also use common ground for large single numbers. For a number to
qualify as a large single number, it must be greater than half of the target
value. If it is less than or equal to half the target value, it is not a large
single number. With a target of 15, any number 8 or higher can be partially
filled in. 8 would get the center block in its rown, 9 the center 3, 10 the
center 5, and so on. If it comes with other numbers, then you can fill more
through the normal common ground rules.

Tip 3: Watch your edges. Just like a jigsaw puzzle, filling in the edges of
your puzzle will make things significantly easier.

1 5 6 --------------O

Oh look, a space is filled in on the right side. That's where our 6 ends. It
is not possible to fill in further right on this, so we can confirm our 6
without doing any math.

1 5 6 --------XOOOOOO

Using the common ground tip, our remaining row value is 7 on a target 8, so we
can fill in as follows:

1 5 6 ---OOOO-XOOOOOO

Without further assistance from the other columns, we won't be able to fill
this row in any further. So let's take a look at a similar example.

1 5 6 ------------O--

It's not right on the edge, but we do have a space marked just enough off it
that we can fill in some of this right now. At most, we can fill in 2 spaces
to the right of our confirm spot, which is not enough to meet the demands the
6 is asking for. So we know that at least 3, and at most 5, spaces left of the
confirm spot can be filled in. So we fill in the minimum it has to be to the
left.

1 5 6 ---------OOOO--

Once we add common ground to this (row 14, target 15), this row will look like
so:

1 5 6 ---OOOO--OOOOO-

One more example before we move on.

3 4 ----------O----

While at first glance, it looks like we can't do anything here, there is
actually a single mark we can make here. This mark is far enough to the right
that the mark cannot be for the 3 (the 4 wouldn't fit), and it's not possible
for us to fill in 4 from the right edge, as that would connect with our
already confirmed space, making it a 5. In a situation like this, we can mark
off the edge as a space that must be empty.

3 4 ----------O---X

Tip 4: Rule of 1. There will be times where you have a row of nothing but 1s.
This is a row you usually can't do anything with on its own and will need help
from other columns, and unless you're looking for it, is usually one you leave
alone. However, something as simple as checking for this can help make serious
strides on your puzzle.

1 1 1 1 1 1 -------O---O---

While doing other columns, you've managed to, without noticing, confirm two
locations on this row. You've run out of other ideas when this catches your
eye. Only ones can fit here, so anything filled in can immediately be
surrounded by X's.

1 1 1 1 1 1 ------XOX-XOX--

May not seem like a lot, but... this can help a lot when combined with another
tip, but that one is so large we'll come to it at the end.

Tip 5: Check for the largest value. This is a bit weird for a tip, but the
essence of this one falls a little in line with Rule of 1, but has more depth
to it.

2 3 2 ----OO----OO---

Now, given the above example, we have two marks of two, but a 3 is missing.
It is not possible, given where the twos are set up, that we can fit a three
in the middle (it would connect with another two), so one of these must be a
three. It is possible for either two to be a three and still fit a two on its
opposite side, so there is nothing we can do here. However, if we have a mark
from another column come in...

2 3 2 ----OOO---OO---

The largest value we have is now filled in everywhere it appears, so two is
now our largest value. And as it so happens, we have a two filled in for us
already. The space to the left of the three, and everything to the right of it
not already confirmed (because all numbers right of that three are completely
confirmed and filled), can now be confirmed to be nothing. Additionally, with
the remaining three spaces, we can invoke common ground to find where one part
of our final two happens to be. So our final mark, before we need help from
other columns, is as follows:

2 3 2 -O-XOOOXXXOOXXX

In short, if you know what your largest value is, and that many spaces in a
row get filled in, you can mark it off, which will help narrow down where each
number may be in the puzzle.

Tip 6: Check for the impossible. This encompasses a large number of things, so
I will only cover a few examples. Essentially, you want to look for things
that simply cannot happen in the puzzle given what you already know for
certain. Let's start with the following:

4 2 --OO--O--------

We have 2 in a row and a 1 with two spaces splitting them off. We can use the
impossible rule to narrow this down significantly. We cannot fill in two
spaces right of the two already filled in because that would connect with the
other filled in spot, making 5 in a row, which is not a valid number to fill.
As a result, we can do the following:

4 2 -OOO--O-XXXXXXX

Since we know where our 4 is, and we already have one space filled in for our
other number, we can confirm that everything beyond one right of our single
fill cannot be anything.

3 --X------------

This is something that comes up quite a bit with rows that have little to
fill. We can use the impossible rule to mark off more spaces than what our
helpful column showed us here. The left two spaces cannot be filled because we
simply cannot fit 3 fills there, so we can mark them off like so:

3 XXX------------

We can do something similar with the opposite scenario, which is also more
helpful than just having an X show up:

3 -------O-------

We only have one number to fill in, and we know where one piece of it is. We
can fill in up to two left or up to two right of this, and everything else is
empty for sure.

3 XXXXX--O--XXXXX

These are more simple examples of the impossible rule. Keep an eye out for
more situations where you can fill in or mark out blocks based on this rule to
make your Picross life easier.

That's all the tips I have for now. Hopefully they'll come in useful. =3 If
anyone would like to contribute their own tips, go ahead and post them in this
thread.