ZeroSpace Factions Guide: Grell, Legion, Protectorate, & Xol
ZeroSpace features four main factions with distinctly different armies, mechanics, and approaches to controlling the battional infantry, vehicles, and mechs, while the Grell spread biomass and overwhelm opponents with evolving alien creatures. The Legion combines expendable soldiers with enormous war machines, and the Xol construct advanced robotic units by merging simpler forms together.
Your main faction determines most of the units available to your army, along with faction-wide talents and topbar abilities. You also select a mercenary faction to supplement that core roster, allowing the same main faction to support several different strategies.
All Factions in ZeroSpace
The four main factions in ZeroSpace are the Protectorate, Grell, Legion, and Xol. All four are available in the Early Access version of the game.
The Protectorate is the most recognizable military force, using specialized infantry, armored vehicles, artillery, aircraft, and heavy mechs. The Grell are an organic faction built around expansion, biomass, infusions, and increasingly dangerous creatures. The Legion sacrifices cheap troops while supporting powerful commanders and some of the largest machines in the game. The Xol are shapeshifting robots that merge basic units into more advanced forms.
Although each faction has a clear identity, none is restricted to a single strategy. Unit choices, talents, heroes, and the mercenary faction paired with your army can significantly change how a match develops.
How Main and Mercenary Factions Work
Your main faction provides the majority of your army. It determines your standard production options, economic structure, faction talents, and major topbar abilities.
Mercenary factions operate as an additional layer rather than replacing that army. They provide supplementary units and tools that can address weaknesses in your main roster or strengthen a strategy it already performs well.
This means choosing the Protectorate does not lock you into one fixed Protectorate build. Pairing it with different mercenaries can provide alternative support units, specialized counters, or new ways to pressure the map. The same principle applies to Grell, Legion, and Xol.
Protectorate
The Protectorate represents humanity’s military presence throughout the Orion sector. Its roster follows familiar science-fiction military roles, combining mobile infantry with armored support, air units, siege weapons, transports, and large late-game mechs.
This is the most broadly adaptable of the four factions. Commandos provide accessible early ranged firepower, while Bastions give the army a close-range frontline option. Sentinels add long-range support, Predators offer speed and mine placement, and Ironwings provide mobile firepower with missiles and sunder capabilities.
The Protectorate becomes increasingly mechanical as it moves into its more expensive units. Hellfires can operate as mobile artillery before entering siege mode, Titans combine ground and anti-air weaponry, and Haulers transport units while supporting nearby forces with healing.
Its late-game roster includes several machines with very different battlefield roles. The Juggernaut is a heavily armored combat platform, the Strider can transport troops and operate in siege mode, the Griffin provides ranged air support, and the Cyclops uses a long-range plasma weapon. The Sol Invictus sits above the normal army as the Protectorate’s enormous ultimate unit.
Protectorate units also benefit from veterancy, giving the faction an incentive to preserve experienced forces rather than treating every engagement as a disposable trade. Pulling damaged units away, repairing vehicles, and maintaining a surviving core can produce a stronger army as the match continues.
The Protectorate is the best starting faction for players who want recognizable unit roles and several viable ways to construct an army. Its roster is easier to understand at a glance than the Xol merging system or the Legion’s sacrifice mechanics, but using its full range of transports, siege units, aircraft, and veterancy still provides considerable strategic depth.
Grell
The Grell are an insectoid and arachnid species living in symbiosis with the plantlike Koru. Rather than establishing a conventional military presence, they spread biomass across the battlefield and prepare new territory for organic growth.
Their army combines small creatures, ambushers, ranged attackers, tunneling units, and enormous biological monsters. Early Grell forces can include inexpensive Stingers and ranged Lashers, while Mandragoras provide a much tougher close-range presence and can tunnel to reposition.
Several Grell units are designed to interact with the environment or attack from unexpected positions. Stingers can submerge in biomass, Lashers possess camouflage, and Threshers can take root before launching powerful long-range attacks. These tools make the faction especially dangerous when it has already established control over an area.
The Grell roster grows substantially more threatening as heavier creatures enter the field. Harbingers attack from range with corrosive projectiles, Keepers can generate additional Arkanids, and Weavers bring long-range biological support. Reavers provide a devastating melee threat, while Behemoths offer a durable ranged platform with support effects.
Infusions are an important part of the Grell identity, allowing their forces to become stronger or more specialized as the player develops the army. Combined with rapid expansion and biomass control, this gives the faction a sense of constant growth. A Grell army that is allowed to spread freely can become much harder to contain than its early units initially suggest.
Choose the Grell if you prefer aggressive expansion, map control, numerous organic units, and an army that evolves as the match progresses. They are particularly suited to players who enjoy establishing favorable territory before overwhelming an opponent with a mixture of expendable creatures and high-impact monsters.
Legion
The Legion is a fanatical empire devoted to the Idals and willing to sacrifice almost anything in service of its cause. That philosophy defines its army, which places cheap and expendable soldiers alongside powerful commanders, heroes, and massive mechanical units.
Thralls form the most basic portion of the Legion army. They are inexpensive ranged troops that can be produced in groups, making them useful for filling out an early force or providing bodies for the faction’s sacrifice mechanics. Steelsworn and Exalted offer more substantial close-range options, while Dark Disciples and Storm Bringers provide long-range support.
The Legion does not remain a light infantry faction for long. Mammoths are enormous melee units capable of disrupting formations, while the Terror Tank is a heavily armed mobile fortress with multiple weapon systems. Dreadnoughts provide another expensive late-game centerpiece with ranged attacks, bombardment, teleportation, and detection.
Sacrifice is more than part of the Legion’s story. Its mechanics reward players for treating lower-level soldiers as resources that can be converted into a larger advantage. Losing a cheap Thrall does not necessarily carry the same strategic cost as losing a veteran Protectorate unit or one of the components needed for an advanced Xol machine.
The faction also has access to numerous heroes and commander-focused strategies. This creates an unusual contrast between its rank-and-file soldiers and its most important units. Basic troops may be sent forward with little concern for survival, while heroes and war machines demand careful positioning and protection.
At the highest level, the Legion can call upon an Emperor Projection, an extremely powerful ultimate unit capable of tearing through enemy forces at close range.
Choose the Legion if you enjoy asymmetric armies, expendable infantry, sacrifice mechanics, and a small number of extremely powerful units. It is a strong fit for players who would rather build their strategy around high-impact commanders and machines than preserve every soldier on the battlefield.
Xol
The Xol are autonomous machines whose defining mechanic is the ability to merge units together. Instead of following a standard progression in which increasingly advanced units are purchased directly from separate production structures, the Xol can combine simpler robotic forms into specialized machines.
The foundational Xol combat units include Rollers, Spectrons, and Xythers. Each has its own battlefield function, but these units also act as components for more advanced creations.
Two Xythers can be used to create a Defiant, a durable melee unit with heavy armor. Two Rollers can form an Echo, while two Spectrons can become a Synapse. These combinations force the Xol player to decide whether basic units should remain active in their current roles or be removed from the field to create something more powerful.
Higher-tier Xol units require even greater commitments. An Eradicator is created from multiple Spectrons and functions as a long-range heavy attacker. A Gravitron is assembled from Rollers and brings shields and battlefield-control abilities. More advanced creations such as the Paradox require existing high-level units as components, turning army production into a branching series of strategic choices.
This system gives the Xol exceptional flexibility, but it also makes losses more complicated. Losing an advanced machine can mean losing both the finished unit and the resources or lower-level bodies used to construct it. Merging too aggressively may also leave the army without enough basic units to cover immediate threats.
The Xol hero Anrubic reflects the same shapeshifting identity. Anrubic can operate in multiple forms, use different versions of its weapon, and access movement and defensive abilities alongside the faction’s merging mechanics.
Choose the Xol if you enjoy planning unit compositions several steps ahead, transforming an army during a match, and making constant decisions about whether to retain basic units or combine them. They are likely the most mechanically unusual faction and may require more familiarity before their production system feels natural.
Which ZeroSpace Faction Should You Choose?
The Protectorate is the strongest starting choice for players who want a balanced and understandable army. Its infantry, vehicles, artillery, transports, aircraft, and mechs occupy recognizable roles, making it easier to identify what the roster is missing during a match.
Choose the Grell if you want to expand quickly, spread biomass, control territory, and attack with a growing organic army. Their mixture of small creatures and enormous monsters favors players who want to build momentum across the map.
Choose the Legion if you prefer sacrificing inexpensive troops while investing in heroes, elite support units, and massive vehicles. The Legion is less concerned with preserving every soldier and more focused on converting losses into decisive advantages.
Choose the Xol if you want the most unconventional production system. Their merging mechanic rewards forward planning and lets the player reshape basic units into increasingly specialized machines as the situation changes.
Best ZeroSpace Faction for Beginners
The Protectorate is the best faction for most beginners. Its units have clearly defined jobs, and its balanced roster allows new players to experiment with infantry, air power, siege weapons, transports, and heavy armor without first learning a unique production mechanic.
Grell is another reasonable starting option for players who naturally favor aggressive expansion and large armies. Biomass and infusions add faction-specific mechanics, but the overall goal of spreading across the map and building pressure is easy to understand.
Legion requires a willingness to sacrifice units efficiently rather than simply producing the strongest army possible. Xol demands the most advance planning because every merge changes both the units gained and the basic forces removed from the battlefield.
What Is the Strongest Faction in ZeroSpace?
There is no single strongest faction for every player or matchup. ZeroSpace armies are affected by unit composition, faction talents, hero selection, mercenary pairing, map conditions, and balance updates.
The Protectorate offers the most conventional versatility, Grell can become oppressive when allowed to establish biomass and expand, Legion can build around devastating heroes and heavy units, and Xol can transform its composition through carefully planned merges.
The strongest choice is therefore the faction whose economy and army mechanics best match how you prefer to play. Learning when to use a faction’s unique mechanic is more important than selecting one based entirely on individual unit statistics.
What to Learn First With Each Faction
Your first few matches should be less about finding the strongest faction and more about understanding what each army expects you to manage. Protectorate players should practice preserving veteran units and combining infantry with the right vehicle support. Grell players should focus on spreading biomass early and learning which creatures benefit most from infusions.
Legion players need to recognize when sacrificing inexpensive troops creates more value than keeping them alive, while Xol players should become comfortable planning merges without stripping too many basic units out of their army at once.
Once those core mechanics begin to feel natural, mercenary choices and faction talents become much easier to evaluate. The best faction to commit to is ultimately the one whose defining decisions remain enjoyable even after the novelty of its unit roster wears off.
