diff --git a/Design-Doc%3A-%60level%60-tool.md b/Design-Doc%3A-%60level%60-tool.md
index e3bec95..ae9266f 100644
--- a/Design-Doc%3A-%60level%60-tool.md
+++ b/Design-Doc%3A-%60level%60-tool.md
@@ -62,7 +62,15 @@ While the above format contains the graphics, this contains the nametable settin
 * This contains entries in [VDP nametable format](https://md.railgun.works/index.php?title=VDP#Nametables), in tile layer B followed by tile layer A, sized according to your settings in Tiled Map Editor. DMA this to the nametable location in each respective layer.
 
 ### .lvc Format (Level Collision Map)
-The collision map is just an array of 8-bit unsigned integers laid out with the same tile dimensions as your visible layers. 0 is a free area, while 1 is a collision area.
+The collision map contains bounding boxes drawn in Tiled editor that your map can check against each iteration of the game loop.
+```
+2 bytes: Number of bounding boxes
+For (Number of bounding boxes):
+   2 bytes: X dimension
+   2 bytes: Y dimension
+   2 bytes: X2 dimension (x + width)
+   2 bytes: Y2 dimension (y + height)
+```
 
 ### .spt Format (Sprite Table)
 The Sprite Table contains a mapping of sprites to tile indices, as well as their tile dimensions and number of animation frames.