So um, yeah. Why is it that sometimes it takes 40 mv to fly up and sometimes it takes 120 mv with a shifter air form? And is there any way of knowing when it would cost more to fly up than usual? Because that sort of stull is kind of annoying when fighting someone and you fly up after they flee out of the area so you can track them only to get stuck up and and like get screwed over. Just wondering.

As a hint, after fighting someone you'll probably notice it's always 120.

My guess is that it is related to terrain.