What is a Critical Hit in 40K?

An unmodified Hit roll of 6 is always a Critical Hit, regardless of modifiers. Both Lethal Hits and Sustained Hits trigger on Critical Hits.

Do Lethal Hits and Sustained Hits work together?

Yes. On a Critical Hit, Sustained Hits generates extra hits and Lethal Hits makes the original hit auto-wound. The extra hits from Sustained Hits are normal hits and still need to roll to wound (unless they are themselves Critical Hits from another source).

Warhammer 40,000 · 10th Edition

Lethal Hits vs Sustained Hits, Explained

A plain-English rules guide

These two weapon abilities both trigger on a Critical Hit, so they get mixed up constantly — but they do completely different things. Here's what each one does, with examples, plus how they behave when a weapon has both.

First: what's a Critical Hit?

An unmodified Hit roll of 6 is always a Critical Hit — no matter what modifiers are in play. Both of these abilities key off that natural 6, so understanding Critical Hits is the whole foundation.

Lethal Hits

Lethal Hits: a Critical Hit automatically wounds the target. You skip the Wound roll entirely for that attack — it goes straight to the target's saving throw.

This is fantastic when your Strength is much lower than the enemy's Toughness. Normally you'd need 5s or 6s to wound a tough target; with Lethal Hits, every natural 6 to hit just wounds automatically, sidestepping the whole problem.

Example — Lethal Hits

Your unit fires 10 shots at a tough vehicle it would normally wound on 5+. You roll to hit and get two natural 6s (Critical Hits). Those two hits skip the Wound roll and wound automatically. The other hits roll to wound as normal.

Sustained Hits X

Sustained Hits X: each Critical Hit scores X additional hits. So Sustained Hits 1 turns each natural 6 into 2 hits, Sustained Hits 2 turns it into 3 hits, and so on.

Those extra hits are ordinary hits — they still have to roll to wound like any other hit. Sustained Hits is about volume: it multiplies how many hits you land, not whether they wound.

Example — Sustained Hits 1

You roll 10 hit dice and get three natural 6s. Each Critical Hit gives +1 hit, so those three 6s produce 6 hits total (3 original + 3 bonus). All of them then roll to wound normally.

When a weapon has both

Some weapons carry Lethal Hits and Sustained Hits together. On a Critical Hit, resolve both: the natural 6 auto-wounds (Lethal Hits), and it also generates extra hits (Sustained Hits). Those extra hits are new, normal hits — they were not themselves rolled as 6s, so they don't auto-wound; they roll to wound as usual.

In short: Lethal Hits improves the quality of a Critical Hit (auto-wound); Sustained Hits improves the quantity (more hits).

Common questions

Do the bonus hits from Sustained Hits also auto-wound with Lethal Hits?

No. The extra hits from Sustained Hits are generated as normal hits, not as Critical Hits, so Lethal Hits doesn't apply to them — they roll to wound as usual.

Does a modifier let me score Critical Hits on a 5+?

Only if a specific rule says so. By default a Critical Hit is strictly an unmodified 6. Some abilities widen the crit range, and those interact with both of these abilities.

Is a Critical Hit the same as a Critical Wound?

No — a Critical Hit is a natural 6 to hit; a Critical Wound is a natural 6 to wound. Anti-X and Devastating Wounds key off Critical Wounds instead.

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 how two abilities interact?

Arbitro is a free AI rules assistant with the 10th-edition core rules built in. Ask it how any weapon abilities stack — it cites its source and says when it isn't sure.

Ask Arbitro a 40K question →