BOOM! Circus Knockdown is out on iPhone and Android
BOOM! Circus Knockdown is now on the App Store for iPhone and iPad and on Google Play for Android phones and tablets. It is a circus cannon physics game, free to start, with no ads and no account. The first four stages also play free in your browser.
The game
Aim the circus cannon, fire, and knock every prop off the table before you run out of cannonballs. Every shot has the same strength, so it all comes down to where you aim.
- Press, aim and release. Or just tap where the shot should land. Drag down to cancel a shot you changed your mind about.
- Real 3D physics. Every block tumbles, slides and bounces its own way. Hit the base and let gravity help.
- Three acts, 48 handcrafted stages. The Opening Act, Balancing Acts and Grand Spectacle. Each act brings new tricks: pendulums, spinners, rising bars, wrecking balls, fire hoops, bomb balloons, falling curtains, spotlights, blackouts, folding shutters, ring posts and a closing press.
- Endless encores. After Act 3 the show goes on with new sixteen-stage acts in ten illustrated themes.
- A live crowd. The stands gasp, cheer and groan with every shot.
What is free, and what Big Top Pass opens
Act 1 is free and stays free: all 16 stages of the Opening Act, replayable as often as you like, with no timers and no daily limits.
Big Top Pass is an optional subscription that opens Acts 2 and 3, the endless encores, and every new obstacle we add. In the US it is $14.99 a year with a free week for new subscribers, or $2.99 a month. If the pass ends, the later acts lock again but your progress stays: cleared stages, the best score and encore progress all wait for you. Restore purchases is on the offer screen.
There are no ads and no account. The game plays offline.
A bot clears every stage before it ships
A physics puzzle has a failure mode a drawn one does not: a stage can look fine and still be impossible. A pendulum may cover the only good line, or a tower may need one more cannonball than the stage gives. So the test suite plays the game.
For every handcrafted stage, a balance check aims and fires the cannon the way a player would, and the stage must be cleared within its shot budget. It waits for a moving obstacle to clear the line of fire, pops the balloons first, leads a catcher to a far corner before it shoots, and on a curtain stage fires again as soon as the props come to rest. Each obstacle is also checked on its own: a badly timed shot must be deflected, a cannonball must fly through a balloon at full speed, and only a clean flight through the hoop sets a ball on fire. If a change to a layout or to the physics makes a stage unbeatable, the tests fail before it reaches a phone.
The carousel only turns the picture
Some stages stand on a turning carousel. The obvious way to build that is to spin the table in the physics world and let friction carry the props. It does not hold: props on a truly rotating table slowly creep apart, and the build you are aiming at is no longer the one the stage was designed as.
So the physics stays still and only the picture turns. Every shot and every blast is converted into the stage's frame of reference, so a cannonball still lands where the turning stage puts the target. The props stay put until you hit them, and the stage still looks like it spins.
One build in three places
The browser game and both apps run the same build of three.js and cannon-es. On the phones, Capacitor puts it in a native shell that sells Big Top Pass: StoreKit 2 on iPhone and iPad, Play Billing on Android.
Android got its own graphics profile. The 3D scene starts at a pixel ratio of 1.5 and steps down to 1.25 once if two windows of 90 frames in a row average below 54 fps, leaving out the slowest tenth of each window so a collapse's physics spikes do not count. There is one step and never a step back up, because each one reallocates the scene's buffers and stalls a modest GPU. On a Moto G Stylus from 2020 the game settles at 1.25 with antialiasing and holds 55 to 60 fps.
The browser version is a demo of the first four stages, and the later stages are not in its download at all: the build swaps in a level table that holds only the demo, then reads the bundle back and fails if a later stage made it in. A flag in the page could be flipped from the console in a minute; a stage that is not there cannot be played.
Get BOOM! Circus Knockdown. Act 1 is free, with no ads and no account.
Play the demo in your browser → See the game and screenshots →