Blocks: decoration, solid, platform, ladder
The Is it solid? setting decides what happens when things touch a Block or a tile. Here is what each choice does.

The four choices
| Just decoration | Only a picture. Sprites walk and fall straight through it. Use it for sky, far hills, bushes. |
|---|---|
| Solid (blocks everything) | Nothing gets through from any side. Walls, floors, ceilings and crates. |
| Platform (jump up through it) | Solid from above only. A Platform sprite jumps up through it, then lands on top. Perfect for ledges. |
| Ladder | A Platform sprite can climb it with the up and down arrows. It is not solid. |
Backgrounds you draw in the Sprite editor use the same list. Library tiles like Grass and Stone Wall come in already solid. Ladder comes in as a ladder.
How to change it
- Click the Block or tile in the level.
- In the panel on the right, find Is it solid?.
- Pick one of the four choices. Every copy of that object changes too.
Which rules notice it
Solid things count as โbackgroundโ in the rules. These tests fire when a sprite meets one:
Collides with a background Is overlapping a background Lands on the ground Is standing on the ground
If you want to know which block was hit, use Collides with another object and choose the Block object instead. That works even for Just decoration, because touching is not the same as being stopped.