Marble Sort Level 399 — Walkthrough and Solution

Marble Sort Level 399 is a puzzle where the bottom row has locked and hidden compartments, and the top tray is shaped like a U. To win, you must first clear the center marbles to expose the Mystery Boxes and find the keys that unlock the Pink Box on the left. The safe colors to start with are Green, Blue, and Purple, but you must avoid Light Blue until a matching box appears.

The bottom has four columns. From left to right: the first column has Purple on top, Blue below it, then Pink at the bottom, but the Pink Box is locked. The second column is all Green with a Pink on top. The third column has Blue on top and three Mystery Boxes below. The fourth column has Purple, Blue, Mint Green, and a Mystery Box at the bottom. In the top tray, the bottom row has dotted Green, Pink, Blue, and Light Purple. Above them are Light Blue, Mint Green, and Dark Blue. The keys are on Black and Orange in the center, plus Orange at the top-left and Brown at the top-right. The left side has Red and Green frozen, and the right side has Purple and Pink frozen.

Marble Sort Level 399 Walkthrough

The front row of bottom boxes demands: first column wants Purple, then Blue, then Pink (locked). Second column wants Green, Green, Green, then Pink. Third column wants Blue, then three Mystery Boxes. Fourth column wants Purple, Blue, Mint Green, then a Mystery Box.

The main trap is the left side: pulling too many Pink or Red early will jam the Conveyor Belt because the Pink Box is locked and you need a key from the center. Also, the Mystery Boxes hide the true targets, so you must uncover them before committing to certain colors.

How to Beat Marble Sort Level 399 — Step-by-Step

Phase one: Clear the center and reveal the first Mystery Box

1. Tap the dotted Green marble from the second row of the top tray and drop it into the second column's Green Box.
2. Tap the dotted Blue marble from the same row and drop it into the third column's Blue Box.
3. Slide the Light Purple marble from the top tray's bottom row into the far-right column's Purple Box.
4. Clear the Purple Box in the first column by dropping the Purple from the top tray into it, exposing the Blue underneath.
5. Drop the Blue marble from the top tray into the first column's Blue Box.
6. Now, clear the Blue target in the third column by dropping the Blue from the top tray into it, which will flip the first Mystery Box—revealing its color.
7. Do not touch any Light Blue marbles yet because no Light Blue box is active.

Phase two: Unlock the Pink Box and thaw the frozen marbles

1. With the center of the top tray hollowed out, you can now access the Black and Orange marbles in the middle. Drop them onto the Conveyor Belt and immediately clear them into any matching open boxes. This activates the Lock and Key and unlocks the Pink Box in the first column.
2. Start clearing marbles that are adjacent to the frozen boxes on the left and right. For example, clear the Green next to the frozen Red and Green, and clear the Pink or Purple next to the frozen Purple and Pink. This will thaw the iced boxes and release the Red, Green, Purple, and Pink marbles.
3. Use the newly thawed Green marble and the Mint Green marbles from the center to empty the second column's Green Boxes completely.

Phase three: Reveal all Mystery Boxes and finish the board

1. As you continue clearing, the remaining Mystery Boxes in the third column will flip. When they do, immediately scan the top tray for those colors and drop them into the corresponding boxes.
2. After the center mass is gone, go for the top-left Orange and top-right Brown marbles, which hold the last keys. Drop them onto the belt and clear them.
3. With the Pink Box unlocked and all targets known, flush the remaining Pink and Red marbles from the top edges into the first column to finish the level.

Tips & tricks

• Focus on clearing the middle of the top tray first to expose the keys and Mystery Boxes.
• Always keep an eye on the Conveyor Belt; if it's nearly full, avoid pulling any new colors until you clear a matching box.
• When a Mystery Box flips, prioritize that color immediately to prevent a backlog.
• Use the thawed marbles wisely to fill multiple boxes of the same color in one go.

Common mistakes

• Tapping Light Blue early when no Light Blue box is open, which jams the belt.
• Ignoring the Mystery Boxes and pulling random colors, causing mismatches.
• Forgetting to unlock the Pink Box before pulling too many Pink marbles, leading to a clog.

Marble Sort Level 399 FAQ

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