I must say its easier to do it than explaining it...
But it doesn't mean i won't help
First how many objects should be created for it?
Answer: just two.
One is t0 mecha and other is t3 ball.
There is jus one thing that mecha should do: opointing a ball.
But ball is a little more complicated.
Lemme explain whats going to be in ball:
First in frames 0 to 9 put your normal flying missile data
then figure out hitting-rebounding frames etc.
We will make the creative part in frames 201 to 399 lol.
Main idea:
balls have different starts but same continues.
A ball will first go up or down or z-up or z-down; then continue normal.
Hit-j tags of ball should be changed for z-moving.
Create frames which goes up-down etc.
For example missle number 1 will go up and z-up and next: 0.
Missle number 2 will just go up and next: 0 etc etc.
Here is the frame sequence which mecha will opoint:
this frame sequence will opoint the starters which a explained above. Then next: 1000 so it will be removed. Also this one won't have pictures and shadow so use pic: 999 and state: 3005.
It's easy, really