Warhammer 40,000: Gladius - Relics of War: Complete Guide

A practical guide to Gladius, Proxy Studios' combat-heavy 4X set on the warp-tainted world of Gladius Prime: how the economy and combat work, how to open with each base faction, what the DLC adds, and the mistakes that lose games.

Researched September 2026 — current as of patch 1.18.01 (June 2026, Eradication Pack). Live games change; check the linked sources if something differs.

Quick Start

1. There is no diplomacy. Gladius is a war game first. Every other faction is an enemy, so plan your economy around feeding an army, not around peace.
2. Clear the wildlife early. The map starts crawling with neutral creatures (Kroot Hounds, Umbra, Enslavers and more). Clearing them near your capital is how you gain early unit experience and safe room to expand.
3. Found your capital fast and grab tiles. Cities claim hex tiles; you can acquire more tiles with Influence and clear forested tiles to make room for buildings.
4. Capture outposts and artefacts. Neutral special features can be taken as outposts, and ancient artefacts give powerful bonuses to whoever holds them. Both are worth fighting for.
5. Recruit a hero early. Heroes gain ranks, unlock abilities and equip items. A levelled hero is often your strongest unit for the whole game.
6. Watch morale, not just hitpoints. Units that take heavy losses lose morale and fight worse. Rotate damaged units back and let fresh ones take the hits.
7. Research economy and your key unit early, then military. Falling behind in tech is recoverable; running out of food or ore mid-war is not.
8. Learn your faction's gimmick. Space Marines have chapter tactics, Astra Militarum have city edicts, Orks build up Waaagh!, Necrons can only found cities on ancient tomb sites. These define how each faction plays.
9. Start on a lower difficulty. The Steam achievements track medium and hard wins separately, so there is no penalty for learning on an easier setting.

What Gladius Is

Gladius is a turn-based 4X on a hex grid. You pick a faction, spawn on a randomly generated world, and fight the other factions plus hostile native life. The base game ships with four factions:

Further factions are sold as DLC: Chaos Space Marines, Tyranids, T'au, Craftworld Aeldari, Adeptus Mechanicus, Adepta Sororitas and Drukhari. There are also many unit packs (Reinforcement, Fortification, Assault, Specialist, Escalation, Firepower, Demolition, Onslaught, Rampage, Eradication), the Ultima Founding pack for Space Marines, and the Lord of Skulls pack.

What changed recently (2025-2026)

The Gets Hot change matters if you lean on plasma-style weapons: overheating now hurts your own units twice as much as before, so do not spam them on low-health units.

Core Systems

Resources

Your empire runs on a handful of resources. Exact yields and names of every building differ per faction, but the roles are consistent:

Rule of thumb: when a resource trends negative, fix it the same turn. Negative stockpiles cripple production at the worst possible moment.

Cities and tiles

• A city sits on its headquarters tile and claims surrounding hexes. Buildings are placed on your city's tiles, and some bonuses reward building next to the headquarters (the "Citadel Miniatures" achievement asks for 20 buildings adjacent to it).
• Acquire additional tiles to fit more buildings and to reach resource features.
• Forested or overgrown tiles can be cleared before building.
• Terrain features on tiles modify what buildings produce, so look at the tile before you place anything.
• Space Marines are limited to one city; most other factions can found more ("Second Foundation" is the achievement for a second city).

Research

Each faction has its own tech tree organised in tiers. You need a number of techs from a tier before the next opens. Good default order:

1. The first economy boosts for your weakest resource.
2. The tech unlocking your first real frontline unit.
3. Hero and item-related techs.
4. A second economy pass, then the units that counter what your nearest rival is fielding.

Heroes

Every faction has several hero units (examples: a Space Marine Captain, an Ork Big Mek, whose shield reduces ranged damage, and an Astra Militarum Lord Commissar, whose Aura of Discipline steadies nearby troops). Heroes:

• Gain experience and ranks from fighting, unlocking stronger abilities.
• Can equip items, from grenades to relics, bought with Influence.
• Are expensive to lose. Keep them behind a screen of cheaper units and use abilities before committing.

Combat basics

• Hitpoints and armour: armour reduces incoming damage; high armour-penetration weapons ignore more of it. Match anti-armour weapons to vehicles and monsters, and high-volume weapons to infantry.
• Morale: units lose morale from damage and nearby losses. Low morale cuts combat effectiveness. Morale recovers when units are out of combat or buffed by heroes and abilities.
• Actions and movement: units typically move and then act. Some abilities let a unit move after an action ("Battle Focused" achievement).
• Overwatch: ranged units can fire at enemies that move into range on the enemy's turn. Advancing into a line of overwatch shooters is how armies die.
• Terrain: difficult terrain slows and hampers most units (check each unit's traits; some, like Tempestus Scions, have an achievement tied to entering it), and some terrain gives defensive bonuses.
• Experience: units level up. A veteran unit is noticeably better than a fresh one, which is another reason to rotate rather than sacrifice.

Native life, outposts and artefacts

• Wildlife is aggressive and scales over time. Early packs are easy experience; later ones can wipe unescorted units.
• Some creatures, like Enslavers, can take control of your units. You can free enslaved units or kill them, and there are achievements for both.
• Outposts are neutral special features you can capture for bonuses and vision. Garrison the important ones.
• Artefacts are ancient relics that give strong bonuses while held. Expect the AI to contest them.

Quests and victory

Each faction has a story questline delivered through quests. Finishing it is tracked separately from winning (for example, "Pyrrhic Victory" for completing the Space Marine story). Conquest, meaning eliminating every rival faction, is the standard way to win; check the victory settings when you set up a game.

Faction Openings (base game)

Space Marines

• One city, so every building slot counts. Acquire tiles aggressively and plan the city layout.
• Units are strong individually; losing any of them early is a real setback. Use the first units to clear wildlife for experience.
• Use chapter tactics to project power across the map instead of expanding with cities.
• Heroes plus a small elite core can snowball; add anti-vehicle options before the first AI tank push.

Astra Militarum

• Expand wide. More cities means more production and more edicts.
• City edicts are your main lever; use them to patch whatever resource is lagging.
• Infantry is cheap and meant to hold lines; tanks and artillery do the killing. The Chimera is useful for moving key infantry and heroes safely.
• Build defensive depth; artillery behind infantry is very strong against the AI.

Orks

• Play aggressively. Orks are strongest when fighting constantly and building Waaagh!, which boosts the whole army when high.
• Cheap melee infantry trades well with wildlife early.
• Flash Gitz and other shooters exist, but the Ork plan is to get into melee quickly.

Necrons

• Cities can only be founded on Necron tomb sites, so scout for tombs first and plan expansion around them.
• Units are slow but tough, so position armies ahead of time rather than reacting late.
• Take fights where durability matters, and avoid being kited by faster armies.

DLC Faction Notes

Only what the in-game systems and achievements confirm:

The T'au note comes from the "For Great Space Communism!" achievement (convert 10 units to your side) and the Aeldari one from "Produce an Avatar of Khaine", so both are confirmed in-game mechanics.

Common Mistakes to Avoid

• Ignoring wildlife near your capital. It blocks expansion and picks off workers and weak units.
• Letting a resource go negative while queuing expensive units.
• Walking into overwatch. Approach in one turn from outside enemy range, or bait fire with a cheap unit first.
• Fighting to the last hitpoint. A retreated unit heals and keeps its experience; a dead one is gone.
• Leaving heroes unequipped. Influence spent on hero items is usually better than an extra marginal building.
• Using overheating weapons carelessly. Since 1.18.00, Gets Hot self-damage is 10%.
• Building outside your faction's strength, like Space Marines trying to trade numbers or Orks turtling.
• Leaving artefacts and outposts ungarrisoned. The AI will take them.

Advanced Tips

• Tempo over perfection. An extra early unit that clears wildlife faster usually outvalues a perfect build order.
• Focus fire. Kill one enemy unit per turn instead of wounding three; damaged units still shoot back.
• Stack debuffs before the big hit. Use hero abilities and morale damage first, then commit heavy weapons.
• Mixed arms. Every army needs something for infantry, something for armour and something to screen. The AI punishes single-type stacks.
• Mind the road network and chokepoints on your side of the map. Fortifications on chokepoints buy time against bigger AI armies.
• Use the new units deliberately. The Eradication Pack added long-range and airborne options for every faction (the Thunderhawk Gunship is a super-heavy airborne transport, the Harpy drops spore mines, Warp Spiders do hit-and-run). They shine when you plan around them rather than dropping them into a frontline.
• Multiplayer: Gladius supports online and hotseat play, with team games against AI. Agree on turn settings up front; simultaneous turns change how overwatch and movement races play out.

FAQ

Is Gladius still being updated in 2026? Yes. The Rampage Pack arrived in December 2025, the Eradication Pack in May 2026, and patch 1.18.01 in June 2026.

Which DLC should I buy first? Pick the faction you want to play. The unit packs add units to factions you own, so they are best once you know which factions you enjoy.

Is there diplomacy? No. There is no diplomacy system; every faction fights every other.

Which base faction is best for beginners? Astra Militarum and Space Marines are the most forgiving. Space Marine units survive mistakes; Astra Militarum has more units to spare. Orks reward aggression, and Necrons require planning around tomb locations.

How do I deal with Enslavers taking my units? Kill the Enslaver quickly with focused ranged fire, or accept the loss and kill the enslaved unit. There are achievements for both.

Can I play offline? Yes. Solo games against the AI work offline. Patch 1.17.2 fixed a start-up bug that mainly affected offline mode.

Was Gladius free at some point? Yes. During the Warhammer Skulls festival (21-28 May 2026) the base game was free-to-keep on Steam. If you claimed it then, you own the base game with its four factions; DLC factions and unit packs are still separate purchases.

Does it support co-op? Yes. You can team up with human players against AI opponents.

Sources

• Steam store page
• Steam achievements list
• Patch 1.18.01 notes (Steam)
• Eradication Pack announcement
• Rampage Pack / 1.17.0 notes
• Patch 1.17.2 notes
• Wikipedia: Warhammer 40,000: Gladius – Relics of War
• Slitherine product page
• Steam Community guides hub