Marble Sort Level 520 — Walkthrough and Solution

Level 520 is the double horizontal lock trap. The Double Horizontal Lock Trap demands patience and precise Conveyor Belt management; the key is to clear only the colors your bottom Boxes request and never touch bait colors early.

Level520
DifficultyHard
Priority routePink → Red
Watch forPink

▶ Video walkthrough of Marble Sort level 520, then the step-by-step below.

⚡ Quick clear

Pink → Red. The lock won't open without its key.

Marble Sort Level 520 throws a massive grid of Mystery Boxes and two horizontal golden bars at you, but the real challenge is resisting the urge to tap tempting colors. The winning strategy is to follow the bottom Box demands strictly: clear Pink and Cyan first, then unlock the keys in order, and finally handle the Mystery Box flood.

The board's Top Tray is seven columns wide, with a playable bottom row of standard marble Boxes. From left to right, that frontline is Dark Red, Light Green, Pink, Blue, Pink, Orange, and another Dark Red. Above that, a solid wall of colors (Dark Green, Yellow, Purple, Cyan, and more) blocks access to the upper Mystery Boxes and the gold locks.

Marble Sort Level 520 Walkthrough

Your bottom receiving area has four slots: the outer two demand Cyan, the inner two demand Pink. The mystery is that the top frontline offers no Cyan, so you must dig for it. The trap is the Dark Red and Light Green: they look safe but have no matching bottom Box, so tapping them early will choke your Conveyor Belt.

The imbalance is clear: the board shows you Pink and Dark Red, but the only safe colors to clear initially are Pink and Cyan. You must ignore the Dark Red entirely and work to expose the Cyan hidden above the Blue and Orange in columns four and six.

How to Beat Marble Sort Level 520 — Step-by-Step

Phase one: Clear the initial Pink and expose Cyan

  1. Tap the Pink Box in the third column of the Top Tray and send it straight down to fill the left inner bottom slot.
  2. Tap the second Pink Box in the fifth column and route it to the right inner bottom slot.
  3. Do not touch the Dark Red on the far left or right, nor the Light Green, because no bottom slot wants them yet.
  4. To reach the Cyan hidden above, tap the Blue Box in column four and drop it onto your Conveyor Belt.
  5. Next, tap the Orange Box in column six and park it on your belt as well.
  6. Now the Cyan tiles above become accessible; tap one Cyan Box and deliver it to the left outer bottom slot.
  7. Then tap the other Cyan and guide it to the right outer slot, clearing the entire first row of bottom Boxes.

Phase two: Unlock the golden bars

  1. As the first row clears, the second row of bottom Boxes appears, demanding Lime Green and revealing Mystery Box slots.
  2. Dig into the Top Tray to expose the key colors: Red, Orange, White, and Blue.
  3. Focus on the lower lock first: find the White and Blue keys. When you expose a White marble, tap it only if a bottom slot requests White, then send it down to unlock the lower bar.
  4. Similarly, handle the Blue key when it matches a bottom slot, and release the Yellow center by breaking the lower lock.
  5. Keep at least three Conveyor Belt slots empty during this phase, because the upper Mystery Boxes will start dropping and could flood you with unexpected colors.

Phase three: Manage the Mystery Box flood and final lock

  1. Once the lower lock is broken, the upper grid of Mystery Boxes becomes playable. Tap one Mystery Box at a time to reveal its color.
  2. If the revealed color matches an open bottom slot or a stranded color on your belt, send it; otherwise, leave it and search for a different safe move.
  3. The bottom tray now demands Orange, Purple, and Lime Green. Clear the Orange you stashed earlier when an Orange slot appears.
  4. Finally, tackle the top lock: find the Red and Orange keys. When you have matching bottom slots, tap those keys to snap the last golden bar and drop the Purple center.
  5. After the final lock breaks, the remaining marbles will cascade into place, so keep your belt clean and finish the level.

Tips & tricks

  • Always check your bottom Boxes before tapping anything; only clear colors that have an open slot.
  • When you must stash a color on the belt, keep an eye on the number of free slots; never let the belt fill completely.
  • Use Mystery Boxes to your advantage: they can reveal the exact color you need, but don't spam them.

Common mistakes

  • Falling for the Dark Red bait early: it has no bottom slot and will clog your belt.
  • Clearing colors randomly to see what's underneath, which leads to a jam.
  • Ignoring the bottom Box demands and focusing only on the top layers, causing mismatched colors.

Marble Sort Level 520 FAQ

Why does my Conveyor Belt flood on Marble Sort Level 520?

It floods because you're tapping colors like Dark Red or Light Green that have no matching bottom Box, filling slots with useless marbles.

Which color do I clear first on Marble Sort Level 520?

Clear Pink first, as two bottom slots request it, then focus on exposing and clearing Cyan.

How many moves does it take to clear Marble Sort Level 520?

There's no fixed move count, but expect to clear around 60-80 marbles, and each tap counts as a move.

Do I need boosters to beat Marble Sort Level 520?

Boosters are not required, but a well-timed shuffler or undo can help if you make a risky stash.

What happens if I tap the Dark Red early on Marble Sort Level 520?

Tapping Dark Red early wastes a belt slot and can lead to a deadlock, forcing you to restart.

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