How the Size-Changing Door works
The door grows wider or narrower as blocks are cleared, changing how much can pass through.
It belongs to the later generation of obstacles: the boards that use it assume you already handle arrows, ice and ropes without thinking, and stack a second rule on top.
How to play around it
Time your exits for the moments when the door is at its widest.
Like every obstacle in the game, the size-changing door never makes a level impossible. Every board can be finished without boosters, so if a route feels blocked, the answer is usually the order in which you clear the other colors, not the obstacle itself.
Where you meet it
The Size-Changing Door typically starts appearing around Level 280 and stays part of the rotation from that point on. Boards that feature it become more frequent as the level numbers climb.
See it in action on the Levels 276–300 walkthrough index, or browse every mechanic on the mechanics guide.
Size-Changing Door FAQ
What does the Size-Changing Door do in Color Block Jam?
The door grows wider or narrower as blocks are cleared, changing how much can pass through.
How do I deal with the Size-Changing Door?
Time your exits for the moments when the door is at its widest.
Which levels have the Size-Changing Door?
It typically starts appearing around Level 280 and is used more often as levels get harder. Open the level walkthrough index to find a video for the exact board you are playing.