Power-up & -down and health bar

  • 19 favourites


Attached Files

The following files have been attached to this tutorial:



Download now 81.64 KB


5,156 visits, 8,545 views



This tutorial hasn't been translated.


This tutorial is licensed under CC BY 4.0. Please refer to the license text if you wish to reuse, share or remix the content contained within this tutorial.

The Basics

Create the game field

Our starting point is:

Feel free to download the following images and insert them accordingly

Layer 0 - Background with background tile

Lock the layer!

Layer 1 - One player sprite, one monster sprite, one medikit to gain health points

Name the sprites accordingly as follows




Place the sprites on the layer and scale them as you prefer. Not we're not building a complete game and only the player sprite is moving.

Side note: don't use the Red Cross symbol on medikits or any other health-related objects. The symbol is protected under the Geneva convention, as you can read here on Wikipedia! Instead, use green crosses or other symbols

Give the player

- an 8Direction behavior with Set angle property set to No

- a new instance variable called health with an initial value of 100

Layer 2 - Text field with Score and two health bars

Note: In a game you program, don't forget to set the layer's parallax properties to 0,0

For the health bar, load the following two images as tiled backgrounds!

Name the tiled backgrounds accordingly as follows and insert Bar_bottom first.



Insert a text object (not a text box!), I used following properties:

Text: Health: 100

Arial, Bold and yellow color

This is what you should see now:

We have to correct the bars now. In their properties, set them both to:

Position 490, 20

Size 100, 20

Adding and subtracting health points

Now that we're set up, let's add some events!

Note: The text field is simply for comprehension of what is happening. In the real game, the health bar suffices and the text would show the score.


When the player is in touch with a monster, health gets diminished. If the player touches the medikit, player's health rises.

So we need to change the Player's instance variable health and the width of the health bar.

Health bar width = 100 × Player.Health / 100

The first 100 corresponds the bar width in pixels. It could be different depending on the bar width you are using.

In the below conditions, the min and max value of the instance variable should be checked as well.


With the following conditions

Monster -> is on collision with another object (choose Player)

Player -> Compare instance variable (Health is greater than 0)

...add these actions

Player -> Subtract from -> Instance variable "health" 1

Text -> Set text -> "Health: "&Player.Health

Bar_top -> set width -> 100[]Player.Health/100*

Save and run the game. Move the player to the monster and each time it hits the monster, the instance variable Player.Health is diminished by 1 and the health bar width is getting smaller and smaller.

But we want a continuous health decline while the player and monster are touching each other. This may depend on your game.

We'll do this with the medikit. Now let's add the following conditions

Medikit -> is overlapping another object (choose Player)

Player -> Compare instance variable (Health is less than 100)

...add these actions

Player -> Add to -> Instance variable "health" 1

Text -> Set text -> "Health: "&Player.Health

Bar_top -> set width -> 100[]Player.Health/100*

Save and run the game. Move the player to the medikit and swooooosh, health is back to 100 in almost no time. You also can observe the Health points getting higher, until it reaches 100.

Now you can change the monster's condition from collision to overlapping.

Don't forget the event when the health variable reaches 0! Game should end or something else should happen. :-)


  • Order by
Want to leave a comment? Login or Register an account!