How to Play

Objective

◎ Be the last player with orbs remaining on the grid. Eliminate all opponents by triggering chain reactions that convert their cells to yours.

Your Turn

▸ Click any empty cell or one of your own cells to place one orb. You cannot place on an opponent's cell.
▸ Turns cycle through all active players. Eliminated players are automatically skipped.

Cell Types & Capacity

Each cell has a capacity based on its position. Exceeding the limit causes an explosion.

1
2
2
1
2
3
3
2
1
2
2
1

sample 4 × 3 grid

Corner — capacity 1, explodes at 2 orbs
Edge — capacity 2, explodes at 3 orbs
Interior — capacity 3, explodes at 4 orbs

Opening Phase

◈ No player can be eliminated until every player has placed at least one orb. This ensures a fair start for everyone.
◈ Enable Cell Capacity Hint in Settings to see each cell's numeric limit on the board at all times.

Critical Mass

◎ When you add an orb that pushes a cell's count over its capacity limit, the cell immediately explodes.

How Explosions Work

The cell empties and fires one orb to each adjacent neighbor — up, down, left, and right.

↑
←
💥
→
↓
Corner cells fire 2 orbs (2 neighbors)
Edge cells fire 3 orbs (3 neighbors)
Interior cells fire 4 orbs (4 neighbors)

Orb Conversion

▸ An orb landing on an enemy cell converts all orbs in that cell — plus the arriving orb — to your color. The cell becomes yours.
▸ Landing on an empty cell simply adds one orb of your color.

Chain Reactions

◎ An incoming orb may push a neighbor cell over its limit, causing it to explode in turn. This cascade continues until all cells are stable.
◎ Even your own cells can be caught in a chain — plan ahead or you may accidentally weaken your own position.
◆ A single well-placed orb can trigger a reaction that sweeps across the entire board in one turn.

Beginner Tips

Corner pressure: Corner cells explode with just 2 orbs and spread in only 2 directions — easy to load up and hard for opponents to defend.
Build clusters: Stack orbs near each other so their explosions chain together across multiple cells in one move.
Watch the orange glow: Cells highlighted orange (Critical Highlight setting) are near critical mass. Yours threaten opponents; theirs threaten you.
Don't overextend: Spreading too thin is risky — an enemy chain through your territory can eliminate you quickly.
Timing matters: Let your opponent load up cells near critical mass, then trigger a chain that flows directly into them.
Multiplayer awareness: In 3+ player games, let opponents weaken each other first. Being last to strike is often better than being the most aggressive.

AI Difficulty Guide

Easy Picks a completely random valid cell every turn. Great for learning the rules.
Medium Greedy strategy — always targets cells closest to critical mass. Plays aggressively but without looking ahead.
Hard Greedy + 1-step lookahead: targets your cells that are one orb from exploding, threatening you directly while building its own chains.

Controls

▸ Click a cell to place your orb on your turn.
▸ Space to pause and resume the game at any time.
▸ Save button stores the current board state (up to 4 slots) so you can continue later.

Select Mode

Player vs AI

Match Settings

Load Game

Save Game

About

Kinetic Reaction 2D is a physics-based strategy game where you place orbs to overload cells and trigger chain reactions.

Conquer the grid by absorbing your opponent's orbs!

Settings

Audio
Sound Effects
Volume
80
Music
Music Volume
50
Visuals
Particles
Anim Speed
Gameplay
Cell Capacity Hint
Critical Highlight
Accessibility
Reduce Motion

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