Designation Force: The 11th-Edition Guard Scout and Sentinel Detachment

One granted ability, and its keyword line is broader than most write-ups admit.

Friendly SCOUT SENTINEL and ASTRA MILITARUM INFANTRY SMOKE units gain Signal Flares: in your Shooting phase, this unit can select one visible enemy unit within 12 inches, and that enemy unit is designated. While a unit is designated, that unit has +3 inches detection range.

Two things are commonly got wrong:

• It is not Scout Sentinels only. It is Scout Sentinels and any Astra Militarum infantry unit with the SMOKE keyword. That is a much larger pool, and it is why cheap infantry squads matter in this detachment rather than just walkers. A basic squad with smoke launchers is a designator.
• It does not strip anything from the enemy. It increases that enemy unit's own detection range, which in 11th edition's detection system makes that unit easier for your army to see and target. It is an offensive tool aimed outward, not a defensive one.

This is the same currency the Abhuman Auxiliaries Sharp Eyes, Light Fingers enhancement trades in from a completely different unit, which is why those two 1 DP detachments complement each other.

What the detachment is really buying you is reach. A Leman Russ or a Basilisk that cannot see a target is not shooting it, and designation is how a handful of cheap forward models convert their position into damage output for the expensive models behind them. The value is positional rather than a raw damage buff, and it rewards pushing scouts into good vantage points early and keeping them alive.

The rule text also states that this detachment has the RECON tag and cannot be taken with another RECON detachment.

Three, all 1CP.

• Close-Range Detection (start of your Shooting phase). Target one friendly SCOUT SENTINEL or ASTRA MILITARUM INFANTRY unit. While a visible enemy unit is within 6 inches of your unit, that unit has +3 inches detection range. This is the aggressive version of the detachment rule: no target selection and no 12 inch limit, just a blanket effect on everything that comes close to your designator. It rewards pushing a cheap unit right into the enemy's face and accepting that it dies there. Note it names ASTRA MILITARUM INFANTRY generally rather than requiring the SMOKE keyword.
• Triggered Alerts (your opponent's Movement phase). When an enemy unit ends a move within 8 inches of a friendly unengaged ASTRA MILITARUM INFANTRY unit, that unit can make a normal move of up to D3+3 inches. A reactive reposition that keeps fragile spotters alive, or moves a squad onto an objective the opponent just vacated. It works anywhere in your army, not just on designators.
• Sump-Smog Screen (start of your opponent's Shooting phase). Target one friendly ASTRA MILITARUM INFANTRY SMOKE unit. When an attack targets either your unit, or a unit that is not fully visible to the attacking model because of one or more models in your unit, the target has the Benefit of Cover against that attack.

The second half is the good half and it is easy to skim past: the screen protects whatever is hiding behind it, not just the unit you targeted. That is what lets a cheap SMOKE squad shield a Leman Russ or an artillery piece for a phase, and it is the reason this detachment is not purely offensive.

The habit to build: designate in your Shooting phase, then hold a point for Sump-Smog Screen in your opponent's, because without the designators alive the detachment stops working.

Two, both 10 points, and both are Upgrades on a unit rather than character relics, so neither needs a Character. That matters here, because this detachment may field no Officer near the front at all.

• Long-range Scout (Upgrade) (10 pts). SCOUT SENTINEL unit only. This unit has Infiltrators. Your designator starts up the board rather than walking there, so Signal Flares is live from turn one instead of turn two.

This is an enhancement, not a stratagem. Mislabelling it as one is the single most common error in community write-ups of this detachment, and our own earlier copy made it. The pack's page geometry is unambiguous: the left column of the detachment page carries the rule and the enhancements, the right column carries the stratagems, and Long-range Scout sits in the left column. - Recon Star (Upgrade) (10 pts). ASTRA MILITARUM INFANTRY PLATOON unit only. In your first Movement phase, this unit can make an ingress move. The counterpart to Long-range Scout: one pushes a Sentinel up the board at deployment, the other brings an infantry squad on early from Reserves.

Which you want depends on whether your designators are walkers or bodies. At 10 points each you can comfortably take both.

(Points come from the Munitorum Field Manual and move with updates; confirm in the app.)

• Scout Sentinels are the first unit the rule names and the only legal carrier of Long-range Scout. The Sentinel kit builds either the Scout or the Armoured variant.
• Armoured Sentinels are the tougher build of the same kit. Note carefully that the detachment rule names SCOUT SENTINEL, so Armoured Sentinels do not get Signal Flares. Bring them as a durable walker, not as a designator.
• [Cadian Shock Troops](/40k/boxes/astra-militarum-cadian-shock-troops) are the cheapest way to field the ASTRA MILITARUM INFANTRY SMOKE half of the rule, which is the half most readers miss. A basic squad with smoke is a designator and a Sump-Smog Screen carrier at once.
• Cadian Recon Squad is the unit the detachment is thematically built around, and one Faction Pack v1.2 prints as a full new datasheet.
• [Krieg Combat Engineers](/40k/boxes/astra-militarum-krieg-combat-engineers) are a forward infantry option that survives being pushed up the board better than a basic squad. The pack rewrites their Remote Mine ability to a 9 inch selection dealing D3 mortal wounds on a 3+, or 2D3 against vehicles and fortifications.
• [Leman Russ Battle Tank](/40k/boxes/astra-militarum-leman-russ-battle-tank) is the gunline this detachment exists to serve. Designation buys reach; a Leman Russ cashes it in. It gains nothing from the detachment rule directly, which is why this is a splash rather than a whole army.
• [Basilisk](/40k/boxes/warhammer-imperial-guard-basilisk-new) is the long-range artillery version of the same idea. The pack rewrites its Earthshaker Rounds ability into a shaken effect that slows an enemy infantry unit it hits.

One buying note. Cadian Recon Squad has no exact entry in our catalog, so we link no box for it.

This is the part to read before you build a 2,000-point recon army, because the list in question is the one the models point at.

Designation Force (1 DP) + [Recon Element](/40k/armies/astra-militarum/detachments/recon-element) (2 DP) costs exactly 3 DP, a full Strike Force budget.

It is illegal. Both carry the RECON tag, and no two detachments in your army may share a Unique Tag. Faction Pack v1.2 states the tag inside this detachment's own rule text, and the Munitorum Field Manual and Wahapedia both record UNIQUE: RECON on both detachments. No source disagrees.

What makes this the best trap in the faction is that the two detachments genuinely look complementary rather than redundant, which is unusual. Most blocked pairings are two versions of the same idea. These are opposites:

• Designation Force is about being able to see: it marks enemy units so they are easier for your army to target.
• Recon Element is about not being seen: under the pack's rewritten rule it gives your entire non-Titanic army Stealth.

A player reads one page about spotting and one about hiding and concludes they are two halves of a recon army. They also share the Reconnaissance Force Disposition, which reinforces the impression.

And there is a timing twist that makes it worse. The Munitorum Field Manual has just decreased Recon Element from 3 DP to 2 DP, printing a decrease marker beside the value. So 1 + 2 = 3 fits a Strike Force budget for the first time, exactly at the moment the tag makes it illegal. Meanwhile a reader working from the community mirror still sees 3 DP for Recon Element, never tries the pairing at all, and so never learns why it is blocked.

The real decision:

• This detachment at 1 DP if you want reach for a gunline and 2 DP left over for something that is not about recon.
• Recon Element at 2 DP if you want army-wide Stealth and a deeper toolkit, at the cost of the marking effect.

We never suggest the pairing anywhere on this site, in either direction. Read the full breakdown.

One pairing that looks blocked and is not: [Mechanised Assault](/40k/armies/astra-militarum/detachments/mechanised-assault) also has the Reconnaissance Force Disposition, which leads people to assume a clash. It carries no Unique Tag in any source and pairs with this detachment freely. A Force Disposition is not a tag.

Take it if you already run a gunline and want it to reach further, and if you enjoy positional play, screening and protecting fragile models. Skip it if you want a straightforward brawl, because it asks you to push and protect cheap scouts every turn.

Be clear-eyed about the limits. The detachment adds no damage of its own. Everything it does is to make the rest of your army shoot better into the right targets, which means it needs a solid 2 DP core doing the killing.

Sample gameplan: pair it with [Siege Regiment](/40k/armies/astra-militarum/detachments/siege-regiment) (2 DP) for exactly 3 DP, which is the strongest thematic fit in the faction. Artillery Support punishes enemy units more than 12 inches from your army, and designation is exactly the tool for finding and hitting things in that range band. Give a Sentinel Long-range Scout so it infiltrates and designates from turn one, take Incendiary Bombardment to strip cover from the marked unit, and hold a point for Sump-Smog Screen to protect the guns.

If you would rather build around tanks, [Hammer of the Emperor](/40k/armies/astra-militarum/detachments/hammer-of-the-emperor) (2 DP) is the other natural fit: eyes in front, guns behind, both moving.

For the fundamentals underneath all of it, read the Astra Militarum army guide.