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docs/reference/game/start-countdown.md

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+# Start Countdown
+
+The game library #docs
+
+The game library supports simple single-player time-based games. The general goal of a game will be to achieve a top score before time runs out of time.
+
+## Block Editor
+
+![](/static/mb/game-library/start-countdown-0.png)
+
+## KindScript
+
+The code below shows a simple game where the user gets to press the button ``A`` as much times as possible in 10 seconds.
+
+```
+input.onButtonPressed("A", () => {
+    game.addScore(1)
+})
+game.startCountdown(10000)
+```
+
+### Score
+
+When a player achieves a goal, you can increase the game score
+
+* add score points to the current score
+
+```
+export function addScore(points: number)
+```
+
+* set the current score to a particular value.
+
+```
+export function setScore(value: number)
+```
+
+* get the current score value
+
+```
+export function score() : number
+```
+
+### Countdown
+
+If your game has a time limit, you can start a countdown in which case `game->current time` returns the remaining time.
+
+* start a countdown with the maximum duration of the game in milliseconds.
+
+```
+export function startCountdown(ms: number)
+```
+
+### Lessons
+
+[bop it](/microbit/lessons/bop-it) | [game of chance](/microbit/lessons/game-of-chance) | [game counter](/microbit/lessons/game-counter)
+