Most quiz questions are a test. You either know the answer or you don't, and the only real variable is who happens to know more.
This one isn't. It's a decision, and decisions are what get a room shouting at each other.
Here's the shape. An image appears on the big screen, obscured. It starts clearing, slowly. Anyone can buzz at any moment, and the instant somebody does, the reveal stops dead. They answer out loud. If they're right, the picture resolves and they take the points. If they're wrong, the reveal starts moving again, now easier for everybody else in the room.
That's it. And the interesting part isn't the mechanic, it's what the mechanic does to the people playing it.
Every second changes the odds
Here's why it works. The information arrives continuously, but the decision is binary. You either buzz or you don't, and you have to keep making that choice while the ground moves under you.
The image is getting easier. The reward for waiting is getting smaller. Buzz too early and you risk looking ridiculous in front of everyone. Wait too long and somebody else takes it. There is a perfect moment, the instant before the next person's hand moves, and you have no way of knowing when that is.
So at three seconds you have a shape, a colour, maybe an edge, and a decision to make on almost nothing. At twenty seconds you're certain, and so is everyone else, and you're not going to be first.
The question has stopped being "do I know this?" It's "how much do I trust what I think I'm seeing, and how long can I afford to wait?" Two teams can both know the answer and get completely different outcomes, because one of them was braver.
That's a different kind of tension from a normal question, and it's why this works as the centrepiece of a round rather than a setting you switch on and forget.
It also punishes the wrong kind of confidence, which is very funny to watch. The person who buzzes at four seconds because they're sure it's the Sydney Opera House, and it's a bowl of pasta, will not be allowed to forget it.
Building one
Three pieces, none of them difficult.
A buzzer question. First to buzz answers out loud, you rule on it. No typing, no multiple choice.
An image with an animated reveal on it. Upload an ordinary photo. You don't need to edit anything: the reveal effect obscures it and clears it for you over a set duration. You can tie that duration to the question timer, so the picture finishes clearing exactly as the clock runs out.
A picture worth the wait. This is the part people underinvest in. It needs to be recognisable at the end and genuinely ambiguous at the start, which mostly means textures and shapes that could be several things. A close-up of brickwork. An unusual angle on something famous. Anything where the first 20% of information actively points somewhere wrong.
Then run it once before the night, with the actual image, and watch when you recognise it. If you get it at four seconds, so will half the room.
Different reveal effects create different kinds of race
How the picture arrives changes how people gamble on it, so this is worth one decision rather than none.
Blur is the honest one. Information arrives smoothly, so the gamble is purely about how much you trust what you're seeing. If you only ever use one, use this.
Grid hands the picture over in chunks, tile by tile. That changes the rhythm completely: nothing happens, then a tile lands and three people lunge for the buzzer at once. The tension comes in pulses instead of a curve.
Spotlight is the cruel one, because a roaming light can cross the answer and move on again while everyone is still thinking. Somebody always sees it and hesitates, and somebody always misses it entirely, and they will discuss this afterwards at length.
One warning on that last one. If the question matters, choose a fixed path rather than a random one. A random light is more fun in principle and will cheerfully wander straight across the answer in the first three seconds, ending your question before it started. A fixed path does the same thing every time, so you can rehearse it and know exactly what the room will see and when.
The other two effects are worth knowing about but do less for this particular format.
Stop the reveal before it finishes
Here's the trick that makes the whole thing land, and almost nobody does it.
A reveal doesn't have to end at a clean image. Run it from fully obscured to only mostly clear, and the picture sharpens while the clock runs but never quite resolves. Nobody ever gets the free answer. The question stays a question right up to the moment you close it.
Then put the real reveal on the answer instead, fast and complete.
So the question teases: enough to argue about, never enough to be certain. And the answer drops: one quick resolve, everyone sees at once, and the room makes the noise you were hoping for. The gap between those two is the whole payoff, and if you let the question finish revealing you've spent it early.
Use it as a change of pace
One or two of these can reset the energy in a round. Everyone is watching the same image and waiting for the next clue, which is a different kind of attention from a normal question, and rooms that have gone quiet tend to come back for it.
Used repeatedly, though, the tension becomes predictable. By the fifth one people have worked out roughly when the picture becomes readable and they wait for it. Save it for the moments where you want the room to sit up.
If you're running teams rather than individuals, expect the arguing to be the point. A team that has to agree before somebody's hand moves is a much better spectacle than an individual quietly deciding.
Two notes
The mechanic isn't unique. Other quiz platforms have built something similar, and that's fine. Good formats don't need to be invented by one platform to be worth using.
Reveal effects are part of Plus. You can build and run the whole thing in a test run for free before deciding anything, which is worth doing anyway, because this is a format you want to have rehearsed.
Try it with an image nobody has seen
The one weakness of a picture reveal is that a familiar stock photo gets recognised early, however hard you obscure it. The fix is an image that doesn't exist anywhere else, which is now something you can just make: Stop Searching for Picture Round Images. Make Them. covers generating one for the answer you have in mind.
An image built for the question, revealed slowly, with a buzzer on it. Build one and see what it does to the room.