Objective Control & Positioning, Explained
A plain-English rules guide, with diagrams
You win 40K by holding objectives, not by kills — so positioning is everything. Here are the three spatial rules that decide games: objective control, engagement range, and unit coherency, each with a diagram.
Objective control
Every model has an Objective Control (OC) characteristic. To decide who holds an objective marker, each player totals the OC of all their models within 3" horizontally (and 5" vertically) of it. The higher total controls the objective — and keeps controlling it even after moving away, until an enemy out-totals them there.
This is why a cheap, high-OC troops unit can wrestle an objective away from a small elite squad — and why Battle-shocked units (whose OC drops to 0) suddenly stop holding ground.
Engagement range
Engagement Range is how the game measures "in combat." A model is within Engagement Range of an enemy if it's within 1" horizontally and 5" vertically. You can't move within engagement range except by charging, and units in engagement range generally can't shoot (with a few exceptions).
Unit coherency
A multi-model unit has to stay together in Unit Coherency: each model must be within 2" horizontally (and 5" vertically) of at least one other model in its unit. Units of 7 or more models have a stricter rule — each model must be in coherency with at least two others, so you can't form a single long conga line.
Common questions
Yes. Once you control an objective you keep control even after moving away, until an enemy has a higher OC total within range of it.
The most common reason is Battle-shock — a Battle-shocked unit has an OC of 0, so it stops contributing to control even while standing on the marker.
If a unit can't be kept in coherency (for example after casualties), you must remove models until it's back in coherency, or move it back into coherency at the next opportunity.
This guide explains the rules in our own words as a reference aid — always confirm the exact wording against Games Workshop's free official 40K core rules for tournament or rules-critical play.
Not sure who holds an objective?
Arbitro is a free AI rules assistant with the 10th-edition core rules built in. Describe the models and ranges and it'll work it out, with a cited source.
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