Ashes of the Singularity II Defenses: Turtling Guide

Defenses in Ashes of the Singularity II are built from your headquarters' build menu, and crucially you can keep placing them even after a region's main building slots are full. The map is divided into regions, each with a limited number of building slots — the headquarters region in Oxide's own dev journal has five — but smaller structures such as vanguard turrets and flak batteries do not consume those main slots. That is the core of turtling: fill a region with buildings, then layer defensive emplacements around them without running out of room. This page walks through how that system works, based on the developer's Defenses and Turtling video dev journal on the game's Steam news hub.

How the region slot system works

Every region on the map can hold only a limited number of buildings or other structures. In the dev journal, executive producer Brett Norton shows a headquarters region that has already used all five of its main building slots, while a side region holds only one and still has four open.

The important part: once a region's main building slots are used up, you cannot add more large buildings there, but you can still open the build menu from your HQ and place smaller defenses. Vanguard turrets along a ridge line, for example, remain available even in a fully slotted headquarters region. So planning a fortified base means budgeting big structures carefully and relying on defensive emplacements for the rest of the region's footprint.

Building your first defenses

1. Open the build menu from your HQ

   Select your headquarters and open its build menu. The defensive options appear there alongside your regular buildings, even in a region with no remaining main slots.

2. Place vanguard turrets where attackers will come

   Pick spots like ridge lines or the approaches to your HQ. Placement is free-form within the region, so line them along natural terrain edges facing the likely attack vector.

3. Queue several at once

   You do not have to place emplacements one at a time. Queue up a batch and the workers fly out and construct them roughly in the order you placed them.

4. Keep your army active while they build

   Defenses take time to finish. In the dev journal the player sends forces to attack a neighbouring region while the turrets construct, using the build-up time productively instead of waiting.

When the emplacements finish, the workers have built a defended headquarters region and you are protected against ground raids on that front.

Anti-air coverage with flak batteries

If you spot hostile jets over your territory, expect an air attack and add flak batteries. They have a fairly large range, but a single battery cannot cover a base whose buildings are spread out. The practical answer from the dev journal: place one flak battery on each side of the spread-out buildings — one near the HQ, another further out — so the combined coverage wraps the whole region and every major structure sits within a wide radius of anti-air.

Two batteries covered the spread-out base in the demo because of the layout. A compact base may need fewer; a very wide one may need more. Judge it by whether your key structures sit inside the shown coverage radius after placement.

Using mortar turrets offensively

Defenses must be placed inside your own region, but their range can reach into enemy territory, and the mortar turret is the clearest example.

1. Research the technology first

   Grab the technology that unlocks the mortar turret for the UEF before you try to place one. Without it, the option is not available.

2. Place them along your region's border

   Put mortar turrets right against the edge of your territory. This is risky — they are exposed there — but their range is long enough to touch the deep parts of the neighbouring region.

3. Let the built-in radar do the targeting

   Once online, mortar turrets expose hostile radar signatures automatically and start firing indirect artillery shells into that range, softening defenders near targets like a relay structure.

4. Attack into the shelled region

   Move an army into the neighbouring region while the shells land. With the defenders softened up, capturing the region becomes straightforward.

The dev journal's summary: just because defenses have to be built in your region does not mean they cannot fire into and harass your opponent's region. Clever, slightly risky placement turns them into a weapon.

Turtling as a winning strategy

The developers state there are late-game defenses with very long range and high impact, so a defensive strategy is viable through the whole match rather than only as an early stopgap. Their own tagline: sometimes defense is the best offense.

One recorded example shows the concept in multiplayer testing. The official Steam announcement hub posted a video blog called Running the Gauntlet, in which two UEF players attack each other through a narrow pass; blocking units and mortar emplacements did heavy damage to closely clustered armoured formations. Terrain like mountain passes and choke points — the Ashfall Caldera map is described as a labyrinth of trenches and gullies with choke points that let defenders hold off otherwise insurmountable odds — magnifies the value of emplaced defenses.

What players are still asking for

Not everything a turtle player might want is confirmed in the game. In the Steam community discussions, players have requested walls, additional defensive structures such as shield generators, and base templating, comparing the game to Supreme Commander. That thread is a feature request, not confirmation, so do not expect walls or shields unless the developers announce them. Players in the same thread also report pathfinding problems on the alpine and tundra maps, with armies and traffic jams struggling in narrow terrain — worth remembering if your defensive choke points rely on unit movement.

• Open the build menu from your HQ — defenses are available even in a fully slotted region
• Queue vanguard turrets along terrain edges facing likely attack routes
• Add flak batteries on each side of a spread-out base once jets appear
• Research the UEF technology before attempting to place mortar turrets
• Place mortar turrets on your region border to shell enemy structures indirectly

Next steps

• The demo walkthrough covers the playable slice where these mechanics first appear, useful for practicing placement before launch.
• The maps page details choke-point terrain like Ashfall Caldera, which determines where your turrets do the most work.
• The army control guide pairs well with the offensive mortar tactic, since it relies on coordinating an army attack into a shelled region.

FAQ

Do defenses use up my region's building slots?

No. Large buildings consume a region's limited main slots, but smaller defenses like vanguard turrets and flak batteries can be placed even after those slots are full, as shown in the developer's turtling journal.

Where should I put flak batteries?

Spread them across your region rather than stacking them in one spot. One battery near the HQ and another on the opposite side gave full anti-air coverage of a spread-out base in the dev journal; flak range is large but cannot wrap a wide layout from a single point.

Can I attack with defenses in Ashes of the Singularity II defenses like mortar turrets?

Yes. Mortar turrets placed along your own region's border have enough range to fire indirect artillery into the neighbouring region, and their built-in radar automatically reveals and shells hostile signatures, letting an army push in behind the bombardment.

Is turtling a viable way to win?

The developers say yes: late-game defenses have very long range and high impact, and their own journals repeatedly frame defensive play as capable of winning — "sometimes defense is the best offense."

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Check note: details on slots, turret placement, flak coverage and mortar turrets come from Oxide's official video dev journal on the Steam news hub and its YouTube release, plus the official Steam store page for release facts and the Running the Gauntlet blog. The pathfinding reports and requests for walls and shields are unconfirmed player feedback from the Steam discussions, not developer commitments.