Groups are a way of making players shoot groups of aliens before they get a pickup. If I have a wave of 5 baddies and wanted you to kill them all before spawning the large coin or powerup, I'd place them all in the same wave and while you could shoot them in any order, you would have to shoot them all, or you'd recieve nothing!

ResetGroup also sets the current group to use, so any START command that uses the Group flag will use the current group. If you want to change the current group for any reason, then you would use SetGroup.

Example: divided we win.

2 Groups on screen at once. Since both groups are on at once, we need to pick different groups so they dont interfere with each other, so the second batch has a group of 1.