pxt-calliope/docs/projects/multi-dice.md

# Multi Dice

## Introduction @unplugged

![Multiple @boardname@ throwing a dice](/static/mb/projects/multi-dice.png)

Build a multi-player dice game using the **radio**. The **radio** blocks let you send wireless messages between a @boardname@ and another @boardname@.

In this game, you shake to "throw the dice" and send the result to the other @boardname@. If you receive a result of a dice throw equal or greater than yours, you lose.

## Dice game @fullscreen

Let's start by rebuilding the **dice** game. If you are unsure about the details, try the **dice** tutorial again.

```blocks
input.onGesture(Gesture.Shake, function () {
    basic.showNumber(Math.randomRange(1, 6))
})
```

## Dice variable @fullscreen

We need to store the result of the dice cast in a variable. A **variable** is like a place in the memory of the @boardname@ where you save information, like numbers.

* Go to the **Variables** toolbox and click ``||Make a Variable||`` to create a new variable. We will call it **dice**. 
* Add a ``||set dice to||`` block and drag the ``||pick random||`` into it.
* Drag a ``||dice||`` from the **Variables** toolbox into the ``||basic:show number||`` block.

```blocks
let dice = 0
input.onGesture(Gesture.Shake, function () {
    dice = Math.randomRange(1, 6)
    basic.showNumber(dice)
})
```

## Send the dice @fullscreen

Put in a ``||radio:send number||`` and a ``||dice||`` to send the value stored in the ``dice`` variable via radio.

```blocks
let dice = 0
input.onGesture(Gesture.Shake, function () {
    dice = Math.randomRange(1, 6)
    basic.showNumber(dice)
    radio.sendNumber(dice)
})
```

## Receive the dice @fullscreen

Go get an ``||radio:on received number||`` event block. This event runs when a radio message from another @boardname@ arrives. The ``receivedNumber`` value is the value of the dice in this game.

```blocks
radio.onReceivedNumber(function (receivedNumber) {
})
```

## Check your cast @fullscreen

Add a ``||logic:if||`` block to test if ``receivedNumber`` is greater or equal to ``dice``. 
If is, you lost so display a sad face on the screen.

```blocks
let dice = 0;
radio.onReceivedNumber(function (receivedNumber) {
    if (receivedNumber >= dice) {
        basic.showIcon(IconNames.Sad)
    }
})
```

## Test it! @fullscreen

Try pressing **SHAKE** in the simulator and see that a second @boardname@ appears. You can play the game on both virtual boards.

If you have more than one @boardname@, download your code onto each one and try playing the game with your friends!

```blocks
let dice = 0
input.onGesture(Gesture.Shake, function () {
    dice = Math.randomRange(1, 6)
    basic.showNumber(dice)
    radio.sendNumber(dice)
})
radio.onReceivedNumber(function (receivedNumber) {
    if (receivedNumber >= dice) {
        basic.showIcon(IconNames.Sad)
    }
})
```

```package
radio
```