Marble Sort Level 307 — Walkthrough and Solution

Level 307 is the lock, key, and mystery box trap. The true challenge of this puzzle is the hidden Mystery Boxes that appear as you clear the board, but if you keep an eye on the Conveyor Belt and follow a strict order, you'll unlock the key and finish smoothly.

Level307
DifficultyMedium
Priority routeOrange → Green
Watch forOrange

▶ Video walkthrough of Marble Sort level 307, then the step-by-step below.

⚡ Quick clear

Orange → Green. Hidden boxes turn every tap into a guess.

Marble Sort Level 307 presents a tricky puzzle with a large Top Tray and four columns of Boxes below. The key to success is to clear the front row in a precise sequence to reveal the Mystery Boxes without jamming the Conveyor Belt. You must prioritize Orange and Dark Green first, then handle Pink/Red, and finally unlock the golden key to release the top marbles.

The board has a heavy chain with a lock at the top center, holding Light Green, Dark Blue, and Yellow marbles. The key to that lock is on the far left edge. The Top Tray's bottom row shows Light Pink on the left, then Pink/Red, Orange, another Pink/Red, and Dark Green on the right. Above that, there are more Light Pink, Pink/Red, Purple, Dark Red, and Blue marbles. In the middle, Iced Boxes freeze Orange, Light Blue, White, Teal, and Purple. Arrow Boxes link Light Green to Dark Green and Yellow to Dark Red. The bottom Boxes are stacked as follows: Column 1 (left) starts with Orange, then two Light Pink Boxes, and a Pink/Red. Column 2 (mid-left) starts with Dark Green, then a Mystery Box, Light Pink, and Green. Column 3 (mid-right) starts with Pink/Red, another Pink/Red, Light Blue, and Dark Blue. Column 4 (right) starts with Pink/Red, two Mystery Boxes, and Orange.

Marble Sort Level 307 Walkthrough

The first moves are critical. You need to clear the Orange and Dark Green marbles from the Top Tray's bottom row to open the first Boxes in Columns 1 and 2. This exposes Mystery Boxes that will demand specific colors, so you must be ready to feed them.

The main trap is the right side of the Conveyor Belt. The two Pink/Red Boxes in Columns 3 and 4 hide Mystery Boxes behind them, and if you pull too many colors too early, the belt will fill up and you'll lose.

How to Beat Marble Sort Level 307 — Step-by-Step

Phase one: Opening Moves

  1. Tap the Orange marbles in the bottom middle of the Top Tray to send them down to the Orange Box at the top of Column 1.
  2. Tap the Dark Green marbles on the bottom right of the Top Tray to clear the Dark Green Box in Column 2, which exposes the first Mystery Box.
  3. Now tap both blocks of Pink/Red marbles from the bottom row of the Top Tray. They will fill the Pink/Red Boxes at the top of Column 3 and Column 4.
  4. After these taps, stop and check the board. Column 4 now shows a Mystery Box, and Column 2 already has one. Do not touch the Top Tray until you see what colors those Mystery Boxes ask for.

Phase two: Unlocking the Key

  1. On the left side, you now have accessible Light Pink and Pink/Red marbles. Tap the Light Pink marbles from the left side of the Top Tray to clear the next Box in Column 1, which is a Light Pink Box.
  2. Look at the Mystery Boxes that are now open. If they require Pink/Red, use the extra Pink/Red blocks you have. If they ask for Light Blue or Dark Blue, you're in a good position because those are near the key.
  3. Move to the far left edge and clear the Light Blue and Dark Blue marbles that are next to the golden key. Only drop them onto the Conveyor Belt if you have the matching Boxes open below.
  4. Once the path is clear, tap the block that holds the golden key. This breaks the chain and releases the Light Green, Dark Blue, and Yellow marbles from the top center.

Phase three: Clearing the Middle and Finishing

  1. Now that the top is open, check the Arrow Boxes. Play the Light Green and Yellow marbles carefully, making sure the Boxes they point to are already cleared before you send them down.
  2. Attack the Iced Boxes in the middle row. You need to clear the boxes adjacent to them to activate them. Work from the left side, dropping the frozen Orange and Light Blue marbles into your open Boxes.
  3. Keep an eye on the Conveyor Belt. If a Mystery Box demands Brown or Purple, use the upper right corner of the Top Tray to fill it. Never let more than two unmatched colors sit on the belt, or the final column will jam. Clear the remaining Pink and Blue stacks one by one to finish the level.

Tips & tricks

  • Always clear the Orange and Dark Green first to reveal the Mystery Boxes early.
  • When you see a Mystery Box, wait until it reveals its color before pulling more marbles from the Top Tray.
  • Use the far left side to unlock the key as soon as you have the Light Blue and Dark Blue boxes ready.

Common mistakes

  • Pulling random colors from the Top Tray without checking the Mystery Boxes can fill the Conveyor Belt.
  • Ignoring the Arrow Box dependencies can cause you to drop a marble that has no open Box.
  • Forgetting to clear the Iced Boxes in time will block your progress.

Marble Sort Level 307 FAQ

Why does my Conveyor Belt flood on Marble Sort Level 307?

The Conveyor Belt floods because Mystery Boxes reveal colors you don't have open Boxes for, so you end up holding too many marbles at once.

Which color do I clear first on Marble Sort Level 307?

You should clear Orange first, then Dark Green, to expose the Mystery Boxes and set up the rest of the level.

How many moves does it take to clear Marble Sort Level 307?

It typically takes about 50 to 60 moves, depending on how quickly you clear the Mystery Boxes and unlock the key.

Do I need boosters to beat Marble Sort Level 307?

No, boosters are not required if you follow the correct order and keep the Conveyor Belt clear, but they can help if you get stuck.

What happens if I ignore the Mystery Boxes on Marble Sort Level 307?

If you ignore the Mystery Boxes, they will reveal colors you can't match, filling your Conveyor Belt and causing you to run out of space.

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