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docs/reference/js/lessons/on-fall/challenges.md

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+# landslide challenges
+
+The on fall function. #onfall #docs
+
+### Challenge 0
+
+Welcome! This [guided tutorial](https://live.microbit.co.uk/td/lessons/on-fall/tutorial) will show you how to detect when the micro:bit is falling. Your goal is to write a program that detects when the micro:bit falls!
+
+```
+input.onFall(() => {
+    images.createImage(`
+. . # . .
+. . # . .
+. . # . .
+. . . . .
+. . # . .
+`).showImage(0) // ***
+})
+```
+
+### Challenge 1
+
+Add a pause within `input->on fall`. This will allow us to display another image in the next challenge.
+
+```
+input.onFall(() => {
+    images.createImage(`
+. . # . .
+. . # . .
+. . # . .
+. . . . .
+. . # . .
+`).showImage(0)
+    basic.pause(2000) // ***
+})
+```
+
+### Challenge 2
+
+Create and display an `X` after the pause from Challenge 1
+
+```
+input.onFall(() => {
+    images.createImage(`
+. . # . .
+. . # . .
+. . # . .
+. . . . .
+. . # . .
+`).showImage(0)
+    basic.pause(2000)
+    images.createImage(`
+# . . . #
+. # . # .
+. . # . .
+. # . # .
+# . . . #
+`).showImage(0) // ***
+})
+```
+
+### Challenge 3
+
+Create a loop so that the micro:bit alternates between the exclamation point and "X" images when the micro:bit falls. You will need a `forever` loop and a pause at the end of the loop to do this.
+
+## See Also
+
+[on shake](/microbit/reference/input/on-gesture)
+