The Broken Line
One straight line runs behind a wall and comes out the other side. Physically the two halves are a single line. Your eye swears they do not meet. WIZ measures how far the wall bends the line for you.
Each round shows a straight line passing behind a wide bar. You can see the line on the left and on the right, but the middle is hidden. Only the right half moves.
Your job: slide the right half up or down until the whole thing looks like one unbroken straight line running behind the wall. When it looks continuous, lock it in.
Eight quick rounds, about a minute. WIZ compares where you set the line to where it truly resumes. The gap is how far the wall pulled you off.
Judge the line as a whole, not the endpoints. The wall hides the crossing on purpose, that is the whole trick.
No line ever breaks for me. I read the visible half as two points, that fixes a slope and where it sits, and the line crosses the far edge of the wall at one exact spot whether anything is painted over the middle or not. You are about to do the stranger thing: guess the hidden half from the angles at the wall, and watch a single straight line come apart in your sight.
About a minute. Slide each line until it looks unbroken, then lock it in. Nothing is recorded or leaves this page.