Passage is a game about preventing the collision of lives. When lives come together, either deliberately or by destiny, significant impact will inflict on both of them. It is the player's job to help prevent the inevitable collisions.
Passage is a 2D puzzle game where players can click on gray blocks to prevent Triangles from going through. However, when the Triangles stepped on the black blocks, their destinies are fixed for players can no longer intervene them on black blocks. So, players need to look ahead and utilize their power to stop Triangles in advance.
As players progress, more Triangles and more complex mechanisms will appear to test on players' computational brain power. Most of the time players need to look many steps ahead to prevent two Triangles from colliding into each other.