A chain reaction strategy is the planning you do before pressing the trigger button on a populated 5 by 5 field: you pick exactly one source unit, predict the discrete tick frontiers that its Manhattan range will create, and confirm that those frontiers actually reach every other unit before you commit. The whole game runs on deterministic rules, so power numbers cap the reach of each wave, candidates activate in stable board-list order, and the Tick recorder prints the exact T0, T1, and T2 groups the simulation produced. The strategic work is therefore not luck but pre-commitment reasoning. Your chain reaction strategy decides whether you clear all units and earn 200 points, or stop early and waste a turn. Five full clears pay the maximum 1,000 points. The reader's task here is simple in form but specific in execution: choose a source whose range reaches a relay whose range reaches a relay whose range reaches the last unit, with branches that cover separate regions rather than chasing a single dead end. You can practise the whole plan on the live Chain Reaction field, which keeps the rules stable across all five experiments and only changes placement, power distribution, and directed reachability.
Why One Source Choice Decides the Whole Field
In a populated field, every unit sits at a fixed grid position with a visible power number from one to three. You do not build a path, place dominoes, or connect adjacent tiles before testing. You choose one source. From that single choice, the field produces a tick-by-tick cascade that either clears every unit or stops early. That means the source choice is the strategic decision; everything after it is computed result data that the Tick recorder displays as T0, T1, T2, and later steps.
The field is already populated, the wave rules never change, and the candidates are always evaluated in the same board-list order. The same trigger on the same field always produces the same tick groups, and a unit activates only once. So the strategy question reduces to a single sentence: which existing unit can start a directed cascade that eventually covers the whole field. The board offers you one decision; the simulation offers you the consequence. The link between the two is your prediction, and the only way to make that prediction sharp is to treat the field as a small graph problem where every edge is a Manhattan distance and every node has an integer power.
Read Power and Position Together
The most common strategic mistake is reading power in isolation. A source with power three sounds strong, but if it sits in a corner where its Manhattan range can only reach weak dead ends, the wave dies on tick two. Conversely, a unit with power one can launch the entire field if it sits at the centre of a relay network, because every tick-one unit it activates then extends the chain in a different direction.
The chain reaction strategy that wins every level treats position as the multiplier on power. Before you select any unit, write down two facts: its grid coordinates and its reach, expressed as the largest Manhattan distance its power number allows. Then scan the field for uncleared units that sit at or inside that distance. The number of reachable units on tick one is your early-frontier size. If that early frontier is one, the source is a dead-end path and you should pick a different one. The beginner path to reading power and position together is detailed in Chain Reaction for Beginners: Read Power, Pick a Source, which walks through the same Manhattan counting routine on the simplest level.
Picture the Reaction as Discrete Frontiers
A chain reaction strategy depends on thinking in ticks, not distances. Tick zero is the source itself. Tick one is every uncleared unit that sits inside the source's Manhattan range. Tick two is every uncleared unit that sits inside the Manhattan range of any tick-one unit, evaluated simultaneously. Tick three comes from the tick-two frontier, and the wave continues until every unit is cleared or the current frontier has no uncleared targets left. Multiple units activated on the same tick form one simultaneous frontier, and only that new frontier emits during the following tick.
Frontier thinking changes your reading of a field. Instead of asking which units the source can reach, you ask what the next frontier will look like. A strong tick-one frontier of three or four units is almost always better than a weak tick-one frontier of one unit, even if that single unit has higher power. Branches are valuable when they cover separate regions of the field, because a single linear chain stops at the first dead end. A remote low-power unit is often the hardest endpoint, so check which relay can reach it before you commit to the trigger. Manhattan distance is the count of horizontal plus vertical steps between two cells, with no diagonal shortcut, so a source at column 2, row 2 with power 2 reaches a target at column 4, row 2 because |2 - 4| plus |2 - 2| equals 2, inside the range. The same source does not reach a target at column 5, row 2 because the distance equals 3, outside the range, so that target must wait for a relay.
How to Pick a Chain Reaction Source
Here is the ordered chain reaction strategy you can apply on every field. The chain reaction game keeps the rules stable and only changes placement, so this routine transfers across all five experiments without modification.
- Inspect every unit's grid position and visible power. Count horizontal plus vertical steps without diagonal shortcuts when you estimate any candidate's Manhattan range.
- Select one source unit by touch, click, or keyboard, then trigger the field. The source emits on tick zero and newly reached units emit together on the next discrete tick.
- Read the recorded tick groups in the Tick recorder. If the wave stops with active units still on the board, the trigger failed.
- Study the last successful frontier and ask which uncleared unit could have acted as a relay. Choose a different source that reaches one of those missing relays, then trigger again.
- Repeat until the tick recorder reaches the final clear. Five cleared fields award 200 points each, totalling exactly 1,000.
The Tick recorder lists every observed wave as T0, T1, T2, and later steps, while cleared units shrink and display the tick on which they reacted. This is computed result data rather than a decorative animation, so treat the tick labels as ground truth when you compare them with your forecast.
Compare Candidate Triggers Before You Commit
The chain reaction game lets you test more than one source, because one failed trigger is repairable. A second genuinely different failed source closes the run, but the identical failed trigger is deduplicated, so a double press does not consume another mistake. That means you have a real budget for thinking before you click.
A practical comparison habit is to pick two candidate sources, predict their tick-one frontier on paper, then choose the one whose frontier branches. A source that reaches a high-power unit in one direction and a medium-power unit in another direction creates two simultaneous sub-frontiers on tick two. A source that reaches two adjacent weak units creates one linear sub-frontier that runs into a dead end by tick three. When you compare two triggers, weight three features in order: frontier size on tick one, presence of a relay that can reach the most distant uncleared unit, and whether any frontier branch covers a previously unreachable region. Power number comes last in the comparison because power only matters inside Manhattan distance. The table below turns that comparison into a quick routine you can run on any new field before pressing trigger.
| Strategic Check | What You Read | What a Strong Choice Looks Like |
|---|---|---|
| Tick-one frontier size | How many uncleared units the source can reach at Manhattan distance within its power | Three or more units, not one dead end |
| Relay reach | Whether any tick-one unit can in turn reach the most distant uncleared unit | At least one tick-one unit covers the farthest cell |
| Branch coverage | Whether tick-two sub-frontiers spread into separate regions | Two branches rather than one linear chain |
| Repair budget | Whether you have one extra source change left for this field | Spend it only on a clearly missing relay |
Treat the choice as a small tournament between two named sources rather than a guess. The mental discipline of comparing the two frontier shapes is what separates a 1,000-point run from a stalled wave.
Repair Strategy When a Trigger Stops Early
The repair mechanic is part of your chain reaction strategy, not a separate phase. When the Tick recorder stops with active units still uncleared, your job is to read the last frontier and identify the relay it missed. The rules are simple and worth memorising: one failed source can be replaced with another, the same failed source is counted only once, a second genuinely different failed source ends the run, and a successful correction clears the failure history before the next level. So the repair budget per field is exactly one, which is why pre-commitment reasoning matters. Spend it on a source whose tick-one frontier clearly points to a relay.
A concrete repair habit is to look at the uncleared units on the board after a stalled wave. Pick the one that sits farthest from any cleared unit. Ask which uncleared unit's Manhattan range could reach it on the next tick. That uncleared unit is the missing relay, and the original source was the wrong choice. Trigger a source that reaches the missing relay, and the wave resumes from a corrected frontier. Because the board is deterministic, you can compare your mental forecast with the exact recorded ticks and understand exactly where an unsuccessful chain stopped.
Score Strategy Across All Five Fields
The five experiments progress from a short three-unit relay to longer fuses, a corner-to-corner handoff, a four-way bloom, and a final multi-branch surge. The grid size and rules never change. Difficulty grows through placement, power distribution, simultaneous waves, and directed reachability, and the independent test oracle locks the complete success set for each level and proves every remaining source stops early. Your chain reaction strategy has to handle all of these shapes without changing the routine.
A safe multi-field rhythm is to spend the first field as a calibration run and use it to confirm your Manhattan counting and tick prediction. From field two onward, apply the same routine: read power and position, pick a source with a tick-one frontier of at least two units, trigger, read the Tick recorder, repair if needed, and move on. The five-field scoring arc is documented in Chain Reaction Game Guide: Score 1,000 Across Five Fields, which goes deeper into the level-by-level cascade shapes. Everything runs locally in the browser, so source choices, tick records, mistakes, progress, and scores are not uploaded and no account or subscription is required to reach the maximum 1,000.