Before making the villain move, we need to adjust everyone’s initial positions to avoid losing health the moment the game starts.
Common enemy behavior patterns fall into two types: “Chasing the Player” and “Teleporting.” Let’s introduce them in order.
9.4.1 Chasing the Player
Before we explain, you might have thought: “Since it needs to chase the player, do we need to know the ‘Player’s coordinates’ and the ‘Enemy’s coordinates,’ calculate the angle of the shortest distance, and then pursue?”
No, no, no. While theoretically correct, practical operation doesn’t need to be that complex. MakeCode Arcade has already figured it out for us.
Let’s click on “Sprites.” Inside the “Physics” section of the list, you can find the “set [myEnemy] follow [mySprite]” block.
Drag this block into “on start.” Click the “+” sign at the end of the block to see the “Speed” setting field. The default speed of 100 makes the enemy as fast as the player—playing at this speed is extremely difficult! You’ll be caught in the blink of an eye. So, please change it to a lower number.
After setting it, test it with the Game Simulator and repeatedly adjust it to a speed you feel is appropriate.
9.4.2 Teleporting
Another method is to make the enemy instantly “Change Position” at a “Fixed Frequency.” For example, setting the enemy to change position every two seconds creates a thrill when the enemy suddenly appears in front of you during gameplay.
We learned how to randomly change positions in previous units. The key is: How do we automatically change the position after a specific interval?
We can use the “on game update every ( 500 ) ms” block found in the “Game” category.
When we set the “Interval,” this block will continuously run the code inside it according to that interval. We want to change the enemy’s position every 2 seconds, so enter 2000 (since the unit is milliseconds) or select 2 seconds from the dropdown menu.
Finally, place the “Random Position” method inside this block. Remember to select the Enemy’s variable name.
Once finished, try playing it in the Game Simulator.
In this unit, we learned about “Life (Health)” and “Animating Sprites.” In addition to the original tension of the time limit, the addition of the villain adds a lot of excitement and fun to the process. Currently, the gameplay mainly involves using the joystick to dodge.
Next, we will add the ability for the character to attack, just like the fighter jet in the “Space Destroyer” example, which can fire beams to destroy meteors.
