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Another Sunday, another NYT Pips puzzle to solve. Today's Medium Pips was quite a challenge, but the Hard really had me stumped. If you're hitting a wall with your domino-laying, read on for a full walkthrough of today's Hard Pips plus solutions for both the Easy and Medium tiers. This was one of the more challenging trio of Pips I've seen in a long, long time.

Looking for Saturday's Pips? Read our guide right here.

In Pips, you have a grid of multicolored boxes. Each colored area represents a different "condition" that you have to achieve. You have a select number of dominoes that you have to spend filling in the grid. You must use every domino and achieve every condition properly to win. There are Easy, Medium and Difficult tiers.

Here's an example of a difficult tier Pips:

As you can see, the grid has a bunch of symbols and numbers with each color. On the far left, the three purple squares must not equal one another (hence the equal sign crossed out). The two pink squares next to that must equal a total of 0. The zig-zagging blue squares all must equal one another. You click on dominoes to rotate them, and will need to since they have to be rotated to fit where they belong.

Not shown on this grid are other conditions, such as "less than" or "greater than." If there are multiple tiles with > or < signs, the total of those tiles must be greater or less than the listed number. It varies by grid. Blank spaces can have anything. The various possible conditions are:

In order to win, you have to use up all your dominoes by filling in all the squares, making sure to fit each condition. Play today's Pips puzzle here.

Below are the solutions for the Easy and Medium tier Pips. After that, I'll walk you through the Hard puzzle. Spoilers ahead.

Look, it's a sailboat! Rare to see a Medium Pips get a fun design like this. I actually considered doing a walkthrough for this one also, but we'll just stick with the solution today:

Here's today's Hard Pips:

This is a deceptively simple-looking Hard Pips. It's mostly just a rectangle, but that one free tile on the right side throws everything akimbo. A few observations before we dive in:

I tried this a few different ways before clearing the board and beginning with the trickiest point on the board: The Pink 5 group. We need to make the number 5 using four tiles. This could be lots of different combinations, but we know that one blank domino is required for the Blue 1 group so we shouldn't count on any blank tiles being used in Pink 5, with just one leftover.

I started by placing the 4/2 domino from Purple = into Pink 5, then laid the 4/4 domino into the remaining Purple = tiles. Next, I placed the 1/1 domino from Pink 5 into Blue 1 (meaning we'll need to have a blank/X domino for the Blue 1 group and free tile -- but we'll save that for last).

Next, I placed the 5/1 domino from Orange = into Pink 5 and the 3/1 domino from Dark Blue 3 into Pink 5. Now we know that our second blank tile has to go in Dark Blue 3. To wrap up this step, I placed the 5/3 domino from Orange = into Green 5.

Finally, place the 2/0 domino from Green 5 into Dark Blue 3 and wrap things up with the 0/4 domino from Blue 1 into the single free tile. And that's all, folks!

This was a very challenging Pips simply because there were so many ways to make that Pink 5 group work. Even when I was certain that 4's were the only number that would work in Purple = and 5's had to be in Orange =, actually placing the right dominoes was a real puzzle. I had tried to use the 4/0 domino from Purple = into Pink 5 but that kept resulting in too few or too many Pips for that group. Oh well, I got there . . . eventually! How did you do?