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In this video, you will change your sprite's looks depending upon the position of the mouse pointer.

You will use key press events and the variable, mouse x.

In today's project, you used the change-effect-by block to make Tera change colors.

To change other effects go to the Looks menu and add another change-effect-by block.

Notice you can also change effects other than the color with this block.

If you choose fisheye, for example, Tera's face seems to swell.

If you choose whirl, Tera turns into a spiral.

This example will use the whirl effect, but you can choose any cool effect you like for your art project.

To better control when effects change, add a when-key-pressed event block and change the drop-down menu to a keyboard letter like C.

Connect a new change-effect-by block to the when-key-pressed block.

Now, when you press the C key, Tera turns in a spiral.

However, the effect never stops, and the sprite never returns to its original state.

How could you get Tera to return to its original form without starting the project over?

Add another key-press-event and change-effect-by block.

Then change the value in the block to a negative number, just like you did in the core project.

To return Tera to its original state, add a key-press-event and the clear-graphic-effects block from the Looks menu.

To make Tera's color change a bit more random, add the variable mouse x from the Sensing menu to the change-effect-by block.

This variable is determined by the mouse's position on the screen.

If you look at the bottom right of the stage, you will see x- and y-coordinates.

When you move the mouse from right to left across the screen, these numbers change from positive to negative and are recorded in the mouse x variable.

You can use mouse x to return your sprite to its original form after the effect.

In this example, once the program starts and the C key is pressed, Tera whirls.

When the mouse moves, Tera changes effects, depending on the position of the mouse.

Test this out in your project, and experiment with different effects, variables, and key-presses.

Now it's your turn.

Experiment with different effects in the change-effect-by block, and choose an effect you like for your project.

Add a key-press-event to control when the effect changes.

Try one of the three options that will make the effect stop and return the sprite to its original state.

Choose an Add-On

Cool Effects

Change the the character sprite’s looks based on the mouse pointer’s position.

Elevator Music

Add background music to the project.

Tiny Tera--Giant Tera

Use arrow keys to make Tera grow and shrink on command.

Arrow Commands

Make the sprite move using the keyboard instead of the mouse.


Create another sprite that can collide with your character sprite.


Add your own costume to your sprite.


  1. Choose an Add-On, and click "watch" to learn how to build it.
  2. Once you finish one Add-On, try another one below the video!