# Help required: Two questions
**URL:** https://forum.makecode.com/t/help-required-two-questions/5732
**Category:** Help
**Created:** [January 25, 2021, 5:42am UTC](https://forum.makecode.com/t/help-required-two-questions/5732 "2021-01-25T05:42:45Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@omnisImperium](https://forum.makecode.com/u/omnisImperium)
#### Post date: [January 25, 2021, 5:42am UTC](https://forum.makecode.com/t/help-required-two-questions/5732/1 "2021-01-25T05:42:45Z")
I have two questions
1: [https://makecode.com/\_Wme8d6MwDEkc](https://makecode.com/_Wme8d6MwDEkc). This is the link to a game I am working on. I have stumbled across an issue in this. As soon as the player leaves the main menu and enters the game, the entire game freezes. I know that this is because of the code that spawns enemies (yes the mySprite/Burgers are the enemies) is causing this issue, but I am unable to understand how to fix this in a quick manner.
2: Is the number entered for the vy / vx velocity of a sprite pixels per second? For example, if I enter 200 as the vx velocity of a projectile, will it travel 200 pixels per second or some other amount per second?
---
### Author:  [@UnsignedArduino](https://forum.makecode.com/u/UnsignedArduino)
#### Post date: [January 25, 2021, 4:00pm UTC](https://forum.makecode.com/t/help-required-two-questions/5732/2 "2021-01-25T16:00:09Z")
1. This is the problematic code:
```typescript
sprites.onCreated(SpriteKind.Enemy, function (sprite) {
while (GameEnded == false) {
if (spriteutils.distanceBetween(player1, sprite) <= 40) {
sprite.follow(player1, 30)
}
})
```
The `sprites.onCreated` function will block until the code ends. Since this is a forever loop, it will pause eternally until it finishes, which is never. So put it in a `timer.background`:
```typescript
sprites.onCreated(SpriteKind.Enemy, function (sprite) {
timer.background(function() {
while (!GameEnded) {
if (spriteutils.distanceBetween(player1, sprite) <= 40) {
sprite.follow(player1, 30)
} else {
sprite.follow(null)
}
pause(100)
}
})
})
```
And also, it seems like you want for the burgers to stop following once a certain distance away, so passing in `null` instead of a sprite will make it stop following it. And you also need to `pause` so that the game loop can update.
---
### Author:  [@UnsignedArduino](https://forum.makecode.com/u/UnsignedArduino)
#### Post date: [January 25, 2021, 4:00pm UTC](https://forum.makecode.com/t/help-required-two-questions/5732/3 "2021-01-25T16:00:13Z")
1. It’s px/sec. (Pixels per second - what else would make sense 😉 )
---
### Author:  [@DahbixLP](https://forum.makecode.com/u/DahbixLP)
#### Post date: [January 25, 2021, 4:23pm UTC](https://forum.makecode.com/t/help-required-two-questions/5732/4 "2021-01-25T16:23:30Z")
1: I am not sure how to fix it but it must be a lot of lag! I have 0 fps… So probably too many enemies spawn!
2: Yes! It is pixel per second! As you can see it says pix/s (Pixel per second)
---
### Author:  [@felixtsu](https://forum.makecode.com/u/felixtsu)
#### Post date: [January 25, 2021, 4:24pm UTC](https://forum.makecode.com/t/help-required-two-questions/5732/5 "2021-01-25T16:24:20Z")
Guessing what you want is,
[https://gameprogrammingpatterns.com/game-loop.html](https://gameprogrammingpatterns.com/game-loop.html)
Put detecting code in ‘update game’ of every game tick