Marathon: Best Faction Upgrades and How to Unlock Them

Most early deaths in Marathon are not about aim. They are about running out of space, sustain, or heat at the wrong moment. The best faction upgrades fix those problems first, and the unlock system has one step almost everyone misses: hitting the rank target does not buy the upgrade for you.

The short version

• Six factions, no “mystery” one: CyberAcme, NuCaloric, MIDA, Sekiguchi, Traxus, and Arachne.
• Best first grind: CyberAcme for storage and heat economy, then NuCaloric for sustain.
• Rank is only half the cost. You raise faction rank by running that faction’s contracts, then still pay Credits plus Salvage to actually buy each upgrade.
• Factions unlock through Liaison Contracts after the Welcome To Tau Ceti intro, so nothing here is permanently missable.
• Chase quality-of-life before firepower. Weapons (Traxus) reward players who already extract consistently.

How faction upgrades unlock in Marathon

You start tied to one faction, and the rest open through Liaison Contracts after the Welcome To Tau Ceti intro contract. Once a faction is unlocked it stays available, so you can build progress across several factions instead of being locked into one irreversible pick.

From there the loop is the same for every faction:

• Unlock the faction through early progression.
• Run that faction’s contracts to earn reputation and raise its rank.
• Open the faction tree and check each upgrade’s requirement.
• Pay the cost in Credits and Salvage materials to buy it.

This is the step most players miss: rank unlocks the option to purchase, not the upgrade itself. You can grind to the right rank and still get stopped at the buy screen because you spent your Credits and Salvage on gear. Keep a reserve. If you are short on materials, prioritize Salvage-heavy contracts so you can actually afford the upgrades you just unlocked. (See our guide to Research Clearance and the Synthsilk Sample for how the material economy ties into faction rewards.)

Recommended faction order for most players

• 1. CyberAcme — storage and heat economy. Helps every run, good or bad.
• 2. NuCaloric — healing and shielding. Makes early mistakes survivable.
• 3. MIDA — mobility and utility, once storage and sustain are handled.
• 4. Sekiguchi — ability cooldown reduction for tactical-heavy builds.
• 5. Traxus — weapons and mods, after your baseline survival is stable.
• 6. Arachne — the PvP-leaning faction; level it once your core needs are covered and your build points you there.

This is not a hard rule. If you already survive fights and just want gun variety, Traxus rises. If your whole plan runs on tactical abilities, Sekiguchi moves up. But for the average player trying to extract more consistently, inventory and survival upgrades return more value than niche power spikes.

CyberAcme: the best first faction for most players

If you want one clean answer for which faction to grind first, it is CyberAcme. Its upgrades target storage and run pacing, which means fewer awkward drop decisions, less wasted loot, and steadier account growth between raids.

• Heat Sink raises your heat capacity, giving you more room to sprint, reposition, and recover before overheating bites — one of the strongest early picks here.
• Locksmith adds keys to your Armory options so you can open locked loot you would otherwise walk past.
• Storage and inventory upgrades matter long-term because between-run space pressure affects everything you keep.

The reason CyberAcme is so safe early: these bonuses help even on bad runs. A weapon unlock feels wasted when you are undergeared or losing fights. More heat headroom and more accessible loot improve both your clean extractions and your messy ones.

Unlock path: clear the required early faction opening, then point your next batch of contracts at CyberAcme until you reach the ranks you need. Hold onto spare Credits and Salvage instead of spending it all on gear — hitting the rank and then being unable to afford the upgrade is one of the most common progression stalls.

NuCaloric: best early survivability faction

NuCaloric is the best second grind for most players, and the best first grind if your core problem is simply staying alive. Its tree is the strongest source of healing and defensive consumables in the early game.

• Patch Kits for reliable healing access.
• Shield Charges to recover faster between fights.
• Shields and related defensive upgrades that make early mistakes less punishing.

This faction earns its spot if you are still learning extraction timing, audio cues, and how hard to commit to a fight. More healing and more shielding let you survive imperfect decisions — which matters more than squeezing extra damage out of a weapon faction when you are not extracting reliably yet.

Unlock requirements follow the same loop: open the faction, run NuCaloric contracts to raise rank, then buy the upgrades with Credits and Salvage. If you play solo or get pulled into drawn-out engagements, move NuCaloric ahead of everything except CyberAcme. NuCaloric’s Introducing: NuCaloric contract is the fastest way into this tree.

MIDA: mobility and utility after your basics are covered

MIDA gets more valuable once storage and survival are already solved. Its tree leans toward mobility and utility rather than raw firepower.

Mobility sounds less exciting than a new gun, but it does more than help traversal: it improves disengages, rooftop routes, fight resets, and extraction timing. If you keep dying because you cannot reposition, MIDA is worth pulling earlier. If you mostly lose head-on fights even from good positions, NuCaloric gives more immediate value.

The trap with MIDA is rushing it before fixing fundamentals. Better movement feels great, but it will not fix limited storage, weak sustain, or a poor heat economy. Slotted in as a third faction, though, it is one of the cleanest quality-of-life grinds in the game.

Sekiguchi: best for ability-heavy builds

The faction’s full name is Sekiguchi (Sekiguchi Genetics) — if you have seen it shortened, that is where the abbreviation comes from, but the in-game faction is Sekiguchi. The reason to level it is ability economy: its standout draw is reduced tactical and trait cooldowns.

If your loadout only uses abilities incidentally, this is not an urgent first grind. If your whole plan revolves around tactical tools, cooldown cuts can outperform generic upgrades because they make your preferred play pattern available far more often. That makes Sekiguchi a specialist faction: very strong for the right build, less universal than CyberAcme or NuCaloric.

Traxus: best weapon and mod progression, but not the best first grind

Traxus is the faction for players who care most about guns and mods, which makes it tempting to rush — especially if you come from shooters where better weapons solve everything. In Marathon that is only partly true. Early runs are usually lost to capacity, sustain, or mobility problems long before pure firepower becomes the bottleneck.

• Standout focus: broader weapon and mod access.
• Best use case: mid-game progression once your survival and run flow are stable.
• Who should prioritize it earlier: confident PvP players who already extract consistently.

Traxus gets much better once you can reliably bring loot home and afford to specialize. Until then, treat it as a third-to-fifth faction rather than a first choice.

Arachne: the PvP-focused faction

Arachne is the sixth launch faction, and it leans toward PvP. It is not a hidden or undocumented tree — it unlocks through the same Liaison Contract loop as the others. The reason it sits last in most progression plans is priority, not mystery: its upside is highest for players who already win fights and want an edge in player-versus-player encounters.

If you are still working on extraction consistency, level Arachne after your storage, sustain, and mobility needs are covered. If you already hold your own against other Runners and want to lean into that, it can move up your list. As with every faction, raise its rank through contracts, then pay Credits and Salvage to buy the upgrades you want.

Common mistakes when chasing faction upgrades

• Hitting the rank but not saving Credits or Salvage. The buy screen still blocks you even after you meet the rank requirement.
• Grinding weapons before quality-of-life. More gun options feel good, but storage, heat, and sustain improve more runs.
• Ignoring faction contracts. General play helps, but targeted contracts are the main route to faster rank gains.
• Overcommitting to one specialized tree too early. Mobility, cooldowns, and weapon mods pay off most after baseline survival is covered.
• Dying before extraction. Upgrades mean nothing if you cannot get out — pair this with our survival tips for staying alive longer in raids.

Practical takeaway

For most players the cleanest route is CyberAcme first for storage and heat, NuCaloric second for survivability, then MIDA, Sekiguchi, Traxus, and Arachne ordered by whether you value mobility, ability uptime, weapon depth, or PvP edge. Remember that rank only unlocks the option — keep Credits and Salvage in reserve so you can buy the upgrade the moment you qualify. When in doubt, pick the upgrade that makes every future run less awkward over the one that only helps in ideal fights.