How does line of sight work in Warhammer 40K?

A target model is visible if you can draw a straight line from any part of the attacking model to any part of the target model, unobstructed by intervening models or terrain that blocks visibility. If at least one model in the target unit is visible, the unit can be targeted.

What does Obscuring terrain do?

Obscuring terrain blocks line of sight through it entirely — you cannot see or be seen through it, even if a sliver of the model is technically visible around the edge.

How does cover work in 40K?

A model with the Benefit of Cover adds 1 to its armour saving throw against ranged attacks. Against AP 0 attacks, a model with a Save of 3+ or better only benefits if it is an Infantry model.

Warhammer 40,000 · 10th Edition

Line of Sight & Visibility, Explained

A plain-English rules guide, with diagrams

"Can I even shoot that?" is the most-asked question in 40K, and it comes down to line of sight. Here's how visibility works, what terrain blocks it, and how cover changes the maths — with diagrams to make it click.

The core rule

A target model is visible to an attacking model if you can draw a straight line from any part of the attacking model to any part of the target model, without that line being blocked by intervening models or terrain that obstructs visibility. If at least one model in the enemy unit is visible, you can target the whole unit.

Line of sight diagram: the attacker can see target A in the open but not target B hidden behind terrain — The attacker can see A (a clear line), but B is hidden — the terrain blocks the line, so there's no line of sight.

Obscuring terrain

The most important terrain trait for visibility is Obscuring. Terrain with this trait — typically Ruins — blocks line of sight through it entirely. Even if you can technically see a sliver of a model around the edge, if the line crosses an Obscuring feature, the target counts as not visible. This is what lets you hide whole units behind ruins.

Cover & the Benefit of Cover

Being visible doesn't mean being exposed. Many terrain features grant the Benefit of Cover, which adds 1 to the model's armour saving throw against ranged attacks (it never improves invulnerable saves).

Cover diagram: a model behind terrain gets +1 to its saving throw — A model with the Benefit of Cover adds 1 to its armour save against incoming fire.

One important exception: against an attack with an AP of 0, a model whose Save is 3+ or better only gets the Benefit of Cover if it is an Infantry model. So a tank in cover gains nothing against AP 0 shots, but infantry always do.

Common questions

Does part of the model peeking out count as visible?

For normal terrain, yes — if you can trace a line to any part of the model, it's visible. But Obscuring terrain blocks the line entirely regardless of a peeking edge.

Can I shoot a unit if only one model is visible?

Yes. You target the unit, and as long as at least one of its models is visible, the whole unit is a legal target — though you can only allocate wounds normally.

Does cover stack with a good save?

It adds 1 to your armour save, but remember the AP 0 exception for non-Infantry with a 3+ save. It never improves an invulnerable save.

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.

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