Suzi Quatro

No matter which way you do this, one of the balls will not be needed - but it's not the same ball each time.

Spoiler: Trick:

ball walking

Suzi Quatro is an American singer / songwriter / bass player from Detroit, and she is credited with being one of the revolutionary leaders of the women in rock movement; before this, women in rock had only been singers (such as Grace Slick and Janis Joplin), but Quatro also played an instrument, which was unusual at the time.
Quatro is listed as hard rock / pop rock / glam rock (she played on the David Bowie song "Heroes"), but she never charted well in the U.S., having bigger success in Europe and Australia. Her best selling album to date in the U.S. is 1980's "Rock Hard", still one of my favorites, though her albums are difficult to find these days, and sometimes expensive.
Quatro played the character Leather Tuscadero in 7 episodes of the TV show "Happy Days", and in 1973, she solidified her 'classic' look, ditching the frilly outfits for leather 'cat suits', usually unzipped to the waist with nothing underneath, and big gold chains. She's still performing, though these days she prefers t-shirts and jeans.
Search Youtube for V6YOhfHwpLQ (Suzi Quatro - "Rock Hard")

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reminded me to this level

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such a good level
to train our softskill about making
correct decision between 2 options,
in relaxing way...
I did it by intended way and through......

Spoiler: shortcut...

pipes or fences could replace
wedge and some grass blocks at those
corner area to prevent ToA and autopilot.
since pipes and fences also dont fill a wholeful
block size, that mean B still able to be squeezed
from below to acces grass block to go to last ball.
replacing the wedge.

Fun, a bit if planning needed before starting to push the balls, .

Is there a spare ball? I didn't need them all, but all the gaps were filled so B could get to the win.

FUN...yes! Thanks for sharing @D.S.Masters

Well B didn`t need all the balls to reach the exit, but he did use all of them anyway ...

Fun fun fun!

@Ray Aznable I was trying to avoid embedding the video...

@Jom There are at least two different ways to do it (perhaps three), and in each case, one of the balls (not the same one each time) won't get used.

@EL797 Not really a red herring, just the way it worked out - there are a couple of different ways to do it, and in each case, one of the balls doesn't get used.

@Don G Rowe The ball riding the rail is cute - that never happened to me during testing, but it doesn't block the gameplay, either. And I guess I should've made it clearer in the first comment that not all balls will be needed, depending on which way you do it - I liked the idea of the options on hitting the balls.

@Ray Aznable I wasn't really worried about ToA... very few people use it, and even fewer like it.

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@D.S.Masters
suzi Quatro video i shared have been deleted.
i got ur massage...
anyway what about autopilot tap on midair ball?

@Ray Aznable You didn't need to delete it... and since I haven't gotten any complaints, I'll probably add videos for some of my levels.
Autopilot tap on midair ball... that can be done, but I'm usually not fast enough to get that move.