Just confirmed with glass off.
Player one, ball one, no switches get the ball back. Doesn’t work on any other ball.
Behaves the same for single or multiplayer games.
4 Likes
This question had me curious, so i just went to the basement and played around with my Ghostbusters Pro a bit with the glass off.
Here are my findings. A lot of this might be common knowledge, and it may or may not be Ghostbusters-specific:
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On Ghostbusters, it is pretty easy to short plunge and get the ball to a cradle on the flipper without hitting any switches, and therefore without qualifying the playfield, and therefore without starting the ball save timer. (not news … i think everyone’s seen this)
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If you drain with the playfield not yet qualified, it gives the ball back and does not auto-plunge, so you can take your time and short plunge again.
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any combination of 3 switches will qualify the playfield, starting the ball save timer, and any subsequent ball you get back will be auto-plunged.
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This i did not know: this 3-switch playfield qualifier counter RESETS each time you drain. so in theory, you can hit two switches and drain, over and over, and never qualify the playfield. infinite ball save!
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any scoop instantly qualifies the playfield.
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the left ramp automatically qualifies the playfield, because it has 5 switches in it, plus the inlane switch (or scoop) the ball ends up at.
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a weak shot into the right ramp can theoretically only hit two switches and therefore not qualify the playfield on its own, but it’d be extraordinarily difficult to do this on purpose. (still, it’d be cool to start PKE Frenzy via the skillshot, drain, and have the playfield not even qualified yet, haha.)
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any shot into the pops will obviously qualify the playfield due to hitting multiple switches.
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the left newton ball, right newton ball, ghost target, proton pack standups, gozer standup (if you can somehow hit it without hitting the pops), terror dog standup, and Slimer are all fair game and count as one switch hit.
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it’s not hard to light all 3 locks before qualifying the playfield on ball one simply by short plunging, hitting the left newton ball, draining, and then doing that again. two hits is all it takes.
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on later balls, you could even light 2x playfield multiplier and super jackpot this way, without qualifying the playfield.
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there are probably even more ridiculous ways to exploit this that i’m not creative enough to come up with.
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the real problem as i see it is the counter resetting after ball drain. if someone drains 3 times without qualifying the playfield, it should be obvious to the software that either something is broken or the player is intentionally exploiting the mechanic. at least, that’s how it seems to me.
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There is an indicator light next to player #…
He literally said the player lights were out on the backbox.
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Outlane doesn’t auto death on Ripleys. When it was in PAPA A and the plunger was removed, I had a few spinner - right outlane and there was nothing I could do about it. Sometimes I got it back, sometimes I didn’t. I suspect it was based on the # of spins.
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CHOOSE AND PERISH! CHOOSE THE FORM OF THE DESTRUCTOR!
And on that day, every car in NYC was totalled due to the right orbit…
Outlanes = insta-qualify. Having learned this the hard way many times myself. 
This is the best use of invalid playfield on GB I’ve pulled off, although avoiding playfield validation is not strictly required:
- Walk up to start 3rd ball, notice that both playfield multiplier targets are qualified
- Short plunge
- Hit 3X playfield target, bricks down the middle
- Short plunge
- Hit 2X playfield target, bricks down the middle
- Short plunge
- Shoot right orbit for 20% score skillshot, which actually awarded 120% due to playfield X (which amounted to about 4 billion points~)
19 Likes
You can definitely get away with some shenanigans on Ripley’s. Here’s what I like to do:
- Short plunge to flippers
- Shoot scoop; hopefully, it will start one of the 2 ball multiball modes (50% chance I think?)
- Trap up ball from scoop (meanwhile, the game deploys a ball to the plunger for multiball, but does not autoplunge it since the playfield is not yet valid)
- Plunge the skillshot with the ball in the plunger
- Play multiball as usual~
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This is not unique to Ghostbusters.
The world is your oyster with invalid playfield. 
One of the important factors here is whether the game has a trough switch. And note I don’t mean the outhole switch, there’s a second switch on the ‘downhil’ of the trough as the ball rolls into the shooter lane. Most gottliebs do, most williams/bally don’t. On a game with this second switch, it’s that switch that increments the ball count, since at the point where the ball hits the switch, gravity will naturally carry it to the shooter lane. On games without this switch, it’s assumed that if the ball reenters the outhole without hitting anything that it must have not made it ‘over the hump’ to roll down to the shooter lane, so it kicks it again. Not sure if this is 100%, but every EM I’ve seen where you can score 0 points has the secondary switch. If I were playing an unknown game in a tournament I’d try to look up the trough from the shooter lane and play carefully should I see that switch.
Also note that, on williams games like Aztec where the bonus starts at 5k, not 0, if you do somehow manage to not validate the playfield, it won’t give you your bonus, and will just give you the ball back, so ‘bonus starts at 0’ is not a good indicator
6 Likes
Another note for modern games is often it’s not just 3 switches to validate, but 3 unique switches. Say, on GoT, if you soft plunge, and the ball hits both slings 500 times and then drains down the middle, that would be a zero-point save, because it only hit the two sling switches.
Jack-Bot is another game where inlanes and outlanes do not insta-validate, so it’s possible to get zero-point save on an outlane drain.
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Spinner outlane on RBION will not validate. However if it hits the switch about halfway up the spinner shot that will validate as a pinguin loop.
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Yep, I lost a match on Target Alpha many years ago (Pinbrawl at Pinball Expo) because of this.
Down by 10 points with 1 ball to play, and didn’t get it.
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Wait, I thought it was Orin that zero-drained Target Alpha with 10 points to go. Were you two teammates that year?
I remember this way too vividly. I think you and I were teammates that year!
All this is invented for the sole purpose of maintaining a stable money grabbing piece of equipment in the wild. Where even the casual-ists of players feel they were not robbed. And where games survive switches going dead or going bananas. That is all there is to it.
Heaven forbid players should a) prefer to play something else or b) kick the machine or, worse of all, c) hassle the staff for a refund.
Hey pinball designers. Get rid of all this when the game is set for competition. Have a nice day.
5 Likes
@bcd: Nope, you and I weren’t teammates that year. I was on a team with Julie, Sergio Johnson, and Scott Sidley. We’ve been enamored with Target Alpha since then, because that insane zero-point drain advanced our team to the finals. But we thought the “guilty” opponent was Orin.
@pinwizj, it seems that pinbrawl.org is offline… do you have the detailed results from these old competitions?
The original PinBrawl site was: www.ournet.md/~pinbrawl
Looks like you can drill down into the detailed results from the past results. I’ll let you and/or @bcd do the digging
https://web.archive.org/web/20060207152615/http://www.ournet.md:80/~pinbrawl/
Yeah lets get rid of possibly one of the most interesting strategy avenues in competitive pinball to evolve over the last 10 years…
Sure some games have made mistakes where valid-playfield expoits feel too much like dicking around (hello CSI) - but I’d argue a game like jackbot is an order of magnitude more interesting and skill based with valid-playfield rules.
I’d rather designers use it as an interesting tool, rather than nuke it from orbit (/looks at lyman 
)
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