So I was making like everyone else and avoiding guides and whatnot... until I came to the underground Marsh puzzles with the blue squares.

I thought I had it, the whole 'create a shape as you would with yellow, then minus the blue' thing. But then, this...

I don't get it.

I sat for HOURS on Photoshop trying to overlay the blue square over a 'chunk' of yellow squares, and just couldn't get any shape to cover all the bottom three yellow ones plus the blue - and then have enough 'left' to 'minus' a full square.

After so long I thought "F this" and went to Youtube (it had been like... 5 hours of doing other puzzles, revisiting, leaving and revisiting again) and the video by PS4Trophies made out like you just 'subtract' the blue amount, regardless of the shape it's in. So you have 12 yellow squares and 4 blue - that means you need a shape of 8 yellow squares, providing it covers the icons?

If you check the vid (13:07 for the timestamp if it hasn't worked) the dude just says "treat it like two L-shapes" because he says you 'do a shape that's 8 blocks big" apparently just shaving off random yellow cubes to make it cover all the icons, regardless of the blue icon's shape.

So, I need help and clarification. Is the blue icon rule that it shows how many squares you don't need to count, and can be subtracted from anywhere on any given yellow shape, or do you minus the shape of the icon as it's shown?

Even with the guy's fairly rushed explanation, I don't get it - and after finally resorting to a guide, it's even more infuriating that it's not clear.

@shalashaskauk666: You minus the shape, in this case a box made of 4 blocks, from the arrangement of yellow pieces required by the puzzle. The only real trick is that you need to include the blue squares icon "behind" the line so to speak. The solution to most of the minus puzzles is bunching up your yellows into a fat block and then chip away with the blue, in the shape they are presented in.

EDIT: Honestly my biggest problem with that area is that a lot of those puzzles really felt like busywork. I actually cut out little paper tetris pieces and drew out a few grids which helped immensely as I was having a hard time visualizing the solutions in my head. This kind of left me with sitting down at the graph paper and moving the pieces around until they finally fit, which for whatever reason didn't feel all that "smart" or "clever" it just felt like solving a weird rubik's cube. Later on there was a puzzle where you need to fit about 7 of those shapes into a very limited space and I sat for over half an hour trying to even make them fit, much less create a working solution - next day I cut out those pieces and solved it on my first try. That said, it didn't feel satisfying like some of the other puzzles.

The one underground portion of the desert sun puzzles also felt like busywork, those who played it probably know what specific part I'm talking about.

@shalashaskauk666

This one stopped me up for a while, but the one after it is infuriating, and actually where I currently am..

For this one the final solution is actually remarkably simple.

You do minus the exact shape in the exact orientation in this case.

The Solution if you want it:

You are subtracting the short legs of the two L shapes. If you pictured it in terms of drawing it you are putting the Ls back on their long sides (3 blocks) with their short sides against each other. If the blocks were dots they'd look like this:

..::..

Remember from earlier puzzles that the tetrominos can swap locations as long as the block identifying them is located within the piece that they contain. So you are swapping the L shapes right and left. This "..::.." shape then has a big 2x2 square in the middle of it. So the final shape ends up having that subtracted from it, leaving you with "....". Meaning the final shape is the 4 remaining long leg pieces across the bottom, then the standing up L piece that contains the blue square shape.

In SUPER direct terms, the solution is:

1 Up, 3 Right, 2 Up, 1 Left, 1 Up, 2 Right, Exit.

Of course the solution only matters if you understand how you got there.

Good luck with the fucking checkerboard nightmare of the next puzzle, which I think will finally lead me to cut out shapes and try to piece them together.

This one threw me for quite a long time too, and I never really "solved" it in the true sense of understanding the pieces.

In the end I realized that, as you said, twelve yellow blocks and four blue means I would need to enclose a space of eight squares. After looking at it for a while, I realized that there was only one configuration of eight squares that would encompass all the block squares and allow me to reach the exit. So I traced it out, and it worked. I never did figure out the true solution that misunderstood genius posted above.

@excitable_misunderstood_genius said:

THANK YOU - okay, so when you subtract the piece, the remaining 'halves' come together to form a shorter line - I was imagining a 'hole' in the shape where the blue was, as oppose to allowing the shape to still be whole.

The one after I followed the dude on that Youtube clip again, but THAT WAS THE LAST ONE. I just needed to get out of that damn room, it felt like I was in solitary confinement haha

Thanks again though man, that helped a lot! The rest of the puzzles in that area I eventually got - as Humanity mentioned - by using graph paper (Photoshop) to visualise everything. I've now activated the laser after a pretty cool final puzzle you have to do.

Onto the next area!

I was stuck on that one for a half hour and thought it was impossible. Went to sleep, woke up and solved it in 2 minutes. For a bit there, I really was tempted to quit.

Anyway, solved this puzzle and haven't played since.

Oddly I spent ages on this puzzle (I had it in the back of my mind when I went to other places too) and when I "solved" it, I was none the wiser. However, when I got to the next puzzle, I solved it instantly. Totally bizarre. Thanks to this thread I finally understand this puzzle and the mechanic (which I'm sure will be helpful later, even though so far every time the blue symbols have appeared since I've solved them pretty quickly).

This is what I believe the actual mechanic of this puzzle is, from when I solved it. The tetrominoes can't be placed outside the board, they can't be moved after placement, and the blue blocks can't be split up that way. What *can* be done is stacking, like this:

0011

0001

0111

1221

That is the placement of the yellow blocks. From there it should be obvious what happens with the blue block. Thus all the rules are followed and consistent, except for this crazy stacking rule that was probably never tutorialized and never used again.

I was actually stuck on this puzzle until yesterday. The thing that helped me was realising that the vertical piece 100% has to go in the upper right corner. From there you just need to find an orientation for the 2 horizontal blocks and swapping their positions creates a 2x2 block that can be removed, so I did that and solved it.

I actually couldn't think about this in the right way at the time so I kind of logically brute forced it. That sounds weird, but basically I counted all of the blocks I would need (12 - 4 = 8) and looked at all the ways I could encapsulate all of the special blocks while maintaining that number. There is really only a couple valid ways to do this in this puzzle, so it only took 2 tries.

Counting the blocks to see how many empty spaces you will have can actually be a very helpful starting point in a couple harder puzzles that have a lot of yellow blocks. It can at least give you a starting point and a better idea of what the final result will look like.