Marble Sort Level 400 — Walkthrough and Solution

Marble Sort Level 400 presents a two-stage lock system: two horizontal golden bars across the center rows freeze part of the board until you drop specific keyed marbles. Your first goal is to clear the Light Blue column to unlock the left bar, then manage the Conveyor Belt while you dig out the remaining keys.

The upper area contains four stacks: Mint Green on the far left, then Light Blue, Magenta, and Orange on the far right. Two Surprise Bags sit at the edges, and two Gift Boxes with a number 3 occupy the top corners. The lower section has four active Boxes waiting for Orange, Light Blue, Yellow, and Brown.

Marble Sort Level 400 Walkthrough

The front row of lower Boxes accepts only Orange, Light Blue, Yellow, and Brown. The Mint Green and Magenta stacks in the upper tray are decoys—do not tap them early or they will sit on the Conveyor Belt and waste space.

The key mechanic is that specific keyed marbles break the golden bars. The left bar unlocks when you complete the Light Blue Box, revealing more keys for the right side. The right bar requires keys from the Yellow and Light Green stacks.

How to Beat Marble Sort Level 400 — Step-by-Step

Phase one: Unlock the left golden bar

1. Tap the Orange box on the bottom right of the upper tray; it falls into the Orange lower Box on the left.
2. Tap the Light Blue box in the second column; it drops into the Light Blue lower Box.
3. Now tap the second Light Blue box that appears (it carries a key); this completes the Light Blue Box and unlocks the first golden bar.
4. Next, tap the Magenta box in the third column to clear it to the Conveyor Belt (a necessary delay).
5. Then tap the Yellow box revealed behind the Magenta; it feeds the Yellow lower Box.

Phase two: Manage Surprise Bags and dig for keys

1. After the Light Blue Box clears, a Light Green lower Box becomes active.
2. Do not touch the Surprise Bags unless you have at least three free Conveyor slots—they drop random colors and can jam you.
3. Focus on the keyed Light Blue box in column two (above the unlocked area) and the keyed Light Green box higher up.
4. If a Surprise Bag reveals Yellow, feed it immediately to clear the front line.
5. The Magenta box you parked earlier will automatically move into the new Magenta lower Box once the Orange Box clears.

Phase three: Pop the Gift Boxes and finish

1. Leave the top corners until last; they trigger naturally as you clear the upper rows.
2. The bottom Yellow and Light Blue Boxes have padlocks that unlock only after the boxes above them are gone.
3. Drop the keyed Dark Green and Red marbles to break the remaining locks.
4. When a Gift Box pops, it releases new colors—pause and check your lower Boxes before tapping.
5. Clear the Brown lower Box on the right to open the final route, then match the Gift Box colors to chain the rest of the clears.

Tips & tricks

• Keep your Conveyor Belt as empty as possible; every free slot is a buffer against Surprise Bag randomness.
• Prioritize keyed marbles over easy matches—unlocking bars opens more space.
• Use the Conveyor Belt to park a marble temporarily if it has no box yet, but only if you have room.

Common mistakes

• Tapping Mint Green or Magenta early clogs the Conveyor Belt and delays your key progression.
• Ignoring the Light Blue column first leaves the left bar locked, preventing access to the rest of the board.
• Popping Surprise Bags without space leads to a flooded belt and no way to clear required colors.

Marble Sort Level 400 FAQ

Get the Official Game

⬇ Download Marble Sort

Back to the full Marble Sort level list.