Marble Sort Level 173 Walkthrough Solution

Marble Sort Level 173 Guide: The Double Key Trap and Bottom Row Bait

This board is a massive trap from the very first tap. You look at the board and see free marbles ready to go. You click them. Boom. Your Conveyor Belt jams, the board locks up, and you fail.

Marble Sort Level 173 is defined by a massive double Lock and Key setup pinning down the center of the Top Tray, combined with a brutal mismatch between the bottom row marbles and the active front Boxes. The dominant colors sitting in your face are Purple, Pink, Brown, Bright Green, and Red. But the board does not want those. The front Boxes are demanding Black, Brown, Yellow, and White.

If you do not strictly control your opening moves and ignore the bait, you will not survive the first twenty seconds.

The Brutal Board Pattern in Marble Sort Level 173

Let’s look at exactly how this board is trying to kill your run.

The Top Tray is split into 5 columns. At the very top of every single column sits a Tunnel. Each Tunnel is marked with a '3'. That means 15 extra marbles are hiding off-screen, waiting to drop down and flood your board later. You have to keep your Conveyor Belt lean to handle that late-game flood.

The middle of the grid is completely paralyzed. Two large yellow keys stretch horizontally across columns 2, 3, and 4. This is a classic Lock and Key obstacle, but its placement here is incredibly aggressive. It physically blocks your access to the dark marbles you desperately need to clear the left side of the board.

Now look down at your bottom Boxes. You have four active slots in the front row:

Far left: Black
Middle-left: Brown
Middle-right: Yellow
Far right: White

Now look back up at the bottom row of the Top Tray. From left to right, you have Purple, Pink, Brown, Bright Green, and Red.

Notice the massive disconnect? Only ONE marble on that entire bottom row matches an active front Box. The Brown marble in column 3.

Everything else is pure bait. Look at the Purple marble in column 1. It looks so easy to grab. But what happens if you drop it? It drops onto the Conveyor Belt and just sits there. The Purple Box is buried in the leftmost queue, completely trapped behind the Black Box. To clear the Black Box, you need Black marbles. Where are the Black marbles? They are trapped in the center grid under the Lock and Key.

If you drop that Purple marble early, you permanently burn a slot on your Conveyor Belt for half the level. You do the same with the Pink or Green marbles? You lose. The order of operations here is absolute.

Marble Sort Level 173 Step-by-Step Walkthrough

You have to open this board with surgical precision. Follow this exact release sequence to clear the bait, crack the keys, and survive the Tunnel drops.

Surviving the Opening Drops in Marble Sort Level 173

The first moves dictate whether you win or lose. We are going to entirely ignore columns 1, 2, and 4 right now.

Grab the Brown marble sitting dead center in the bottom row (column 3). Send it straight down into the middle-left Brown Box.
Leave the Purple, Pink, and Green bottom-row marbles completely alone. Do not touch them.
Clearing that Brown Box shifts the middle-left queue forward. It reveals a Red Box.
You have a free Red marble sitting on the bottom right (column 5). Tap it instantly to start filling that Red Box.
Now you have a gap pushed up in column 3. This is your window. Look at column 1, row 2. There is a Yellow marble sitting right above the bait Purple marble.
You need that Yellow marble for the middle-right Yellow Box. Drop the Purple marble onto the Conveyor Belt (just one is fine now), then immediately grab the Yellow marble and send it to its Box.

Breaking the Lock and Key in Marble Sort Level 173

With the Yellow and Brown boxes out of the way, the middle of the board starts to breathe. Now you must attack the center trap.

Your next priority is the Black Box on the far left. Dig into the newly exposed marbles in columns 3 and 5 to find the Black marbles.
Routing Black marbles into the Black Box is the key to this level. As you clear the surrounding marbles in the center grid, you will activate the pegs holding the Lock and Key.
Focus on clearing the specific marbles anchored to the key mechanisms. Once both keys break, the center of the Top Tray visually shatters, opening up columns 2, 3, and 4 completely.
Do not panic-click the newly freed center marbles. Look at your bottom Boxes. Clearing the Black Box pulled the Purple Box to the front.
Now is the time to finally use that bait Purple marble you parked on the Conveyor Belt earlier. Slam the remaining Purple marbles into the left-side queue.
Clearing the Purple Box reveals a Green Box. Take the Bright Green marble from the bottom of column 4 and send it home.

Managing the Final Tunnels in Marble Sort Level 173

As you clear the visible board, you will inevitably push up to the top row. This triggers the Tunnels.

The five Tunnels (marked with '3') will begin dispensing marbles. They will drop heavy clusters of Pink, Light Blue, and White marbles.
Do not open all five Tunnels at the exact same time. If you strip the top row entirely, all five Tunnels will drop random colors onto the board at once, instantly overcrowding your remaining match options.
Focus on the rightmost bottom Boxes. The queue over there is White, Purple, Purple. You want to clear that White Box fast so you have an active Purple slot ready for the Tunnel drops.
Pace yourself. Pull a Light Blue marble from a Tunnel only if the Light Blue Box (buried third in the middle-right queue) is actually active or about to be active.
Keep at least three slots open on your Conveyor Belt at all times during this phase. If a Tunnel drops an orange or dark grey marble that you don't immediately need, let it sit up top.
Clear the bottom Boxes column by column to maintain control, and the final Tunnel marbles will sort themselves easily.

Marble Sort Level 173 Walkthrough Solution | Marble Sort 173