Games Development Enrichment
Scratch
The Impossible Game
An advanced technique in Scratch is the changing of levels. Changing levels is difficult in
Scratch as your program must include the sprites from all of the levels of your game and
work out which to display at any given time.
We are going to implement The Impossible Game in Scratch to illustrate how levelled
games can be created.
1. Start a new Scratch project and delete
the cat sprite.
Create the shown variables.
2. Create the backdrops shown. It is
important to use the same shades of red
and green throughout all 3 backdrops.
Call the backdrops Backdrop1,
Backdrop2 and Backdrop3.
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Games Development Enrichment
Scratch
3. Create the sprites shown. Each of the
enemy sprites should be the same
shade of blue.
Size the enemy sprites so that they fit
reasonably into the appropriate
backdrops
One big sprite:
Implementing enemies that move
in the same way as one big sprite
makes the game much simpler to
create. We only have to write
one script to move it. Carry out
rotation for the individual blue
dots would be particularly hard.
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Games Development Enrichment
Scratch
4. Add the script on the right to the player
sprite.
X and Y positions:
Your levels will probably be
slightly different from the ones
in the demonstration game.
You’ll have to work out the
correct x and y for the go to
blocks based on your own game.
Make sure there is space on the
level for the x and y you use on
every level.
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Games Development Enrichment
Scratch
5. Add the scripts on the right to the L1
Enemy sprite.
6. Add the scripts on the right to the L2
Enemy sprite.
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Games Development Enrichment
Scratch
7. Add the scripts on the right to the L3
Enemy A sprite.
8. Add the scripts on the right to the L3
Enemy B sprite.
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Games Development Enrichment
Scratch
9. Add the scripts on the right to the Stage.
10. Test your game.
Extension
The level variable tracks which level the player is on. Each sprite is always
examining the level variable to decide if it should display itself or not. This is one
of the simplest ways to change the appearance of the scratch screen.
Now that you have seen this working in your program, try to add additional levels
to your game.
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