About this game

Particle Push is the game that exercises the engine hardest. Every particle is a real body that collides with every other one, which means a packed group transmits your push through the pile rather than each particle responding individually.

The repulsor uses a linear falloff rather than an inverse-square one, which is a deliberate design choice: its edge is a sharp, readable circle. An inverse-square field would blow the swarm apart the moment you got close, and the game would stop being about herding.

How to play

  1. Move the cursor with the pointer or the arrow keys.
  2. Hold to push. Everything inside the circle is pushed away from the centre.
  3. Herd particles into the green pen on the right. It is open on one side.
  4. Reach the quota shown in the HUD before the clock runs out.
  5. Six rounds complete the run.

Physics mechanics

Here is what the simulation is actually doing while you play.

Linear-falloff repulsion

Force is proportional to (1 − distance/radius), reaching exactly zero at the edge of the circle. That makes the field's reach visible and predictable, which is what herding requires.

Particle-particle collisions

The particles collide with each other, so a push applied to the back of a group propagates forward through contacts. Pushing a crowd is genuinely more efficient than pushing individuals.

Damping

Each particle carries a linear damping term, so a swarm eventually settles rather than bouncing forever. Without it, the pen would never hold anything.

Broad-phase collision

With 34 bodies the engine switches from brute-force pair testing to a uniform spatial hash, which keeps the cost manageable on a phone.

Why a crowd moves as one

Individual particles are light, so a single one shoved hard just shoots away. A packed group behaves completely differently: each particle passes part of its momentum to its neighbours through collisions, so the group's combined mass resists and it moves as a slower, more controllable unit. That is why compacting the swarm before pushing it is faster than chasing strays, and it is the closest this catalogue gets to modelling granular flow.

Objective

Get the required number of particles into the pen before the timer expires.

Scoring

  • Each particle entering the pen scores 80 points.
  • Clearing a round awards 400 points plus 22 points per second remaining.
  • Particles that leave the pen stop counting, so a scattered push can cost you score.

Scores, favourites and play history are stored in your own browser using localStorage. There is no account, no leaderboard and no server: clearing your browser data clears them, and they do not follow you to another device.

Tips

  1. Push from behind. Place the cursor on the far side of the group from the pen. Everything in the circle moves directly away from you.
  2. Use the crowd. A dense group transmits force through contacts. Compacting the swarm first and pushing once is faster than chasing strays.
  3. Do not push into the pen wall. The pen has a solid back. A hard push scatters particles off it and back out of the opening.
  4. Round up strays early. A particle alone in a corner takes as long as ten in a group. Collect them before the crowd gets close to the pen.
  5. Short pulses near the pen. Once particles are near the opening, small taps steer them in. A long hold blows them straight past it.

Difficulty

Medium. The physics is forgiving and there are no instant-fail hazards — only the clock. The difficulty comes from the quota rising with the particle count and from obstacles that make a single clean push impossible in later rounds.

Features

  • Up to 34 interacting bodies solved with a spatial-hash broad phase
  • Linear-falloff repulsor with a visible, hard-edged radius
  • Open-sided collection pen that has to be steered into
  • Obstacle pillars that scatter a badly aimed push
  • Six rounds with rising particle counts and quotas

How accurate is this?

Physics Arcade games use simplified, tuned physics built for playability. They are not scientific simulations: forces, masses and timings are chosen because they feel good at 60 frames per second, not because they match measured values. Where a game departs from real-world behaviour in a way that matters, the game page says so.

Particle Push – FAQ

Can I pull particles towards me?

No. The field only repels. Steering is done by choosing where you stand relative to the group, which is the core constraint of the design.

Why does the swarm scatter when I push hard?

Force falls off with distance, so particles at the centre of your circle get pushed much harder than those at the edge. Standing further back gives a more even push.

Do particles ever leave the pen?

Yes, if you push them out. The counter reflects what is inside the pen right now, not what has ever been in it.

Why does the frame rate hold up with so many objects?

The engine switches to a spatial-hash broad phase above 40 bodies, which avoids testing every pair against every other pair.