How do I increase game speed and spawn rate

Hello everyone,

In my game currently I have blocks that scroll from the top of the screen to the bottom. I have their scroll rate set to a global variable and their spawn rate set to random(0.5,1.0). Every 5 seconds I add 100 to the scroll rate global variable so that the blocks scroll faster. The problem is that I don't know how to speed up the spawn rate in comparison. So instead of the game becoming harder as the it speeds up, right now it is becoming easier and that is a problem.

(if anyone's played don't step on the white tile, you know how every few seconds the tiles speed up but the spawn rate of the tiles speed up as well. That is what I am trying to achieve.)

Thanks for any help

use variables for your minimum and maximum values in the random() expression. So have min = 0.5 and max = 1.0, then do random(min, max) and when you change those variables values the spawn rate will increase with it.

Thanks for the reply, by variables do you mean global variables?

they can be local, but yes thats what I mean.