The Faction System at a Glance: Which Faction Gives You What

The two tracks: friendly and hostile

Every faction is either one you earn Reputation with - or one that racks up Infamy against you.

• ▸Friendly factions accrue Reputation from quests, bounties, and kills of monsters hostile to them, tracked per character and per faction.
• ▸Ranks run Friendly (from 1,501), Respected (5,001), Honored (10,001), Revered (25,000), each unlocking the next tier (1-4) of the faction shop.
• ▸Hostile factions accrue Infamy. The downside is minor, and at 20,000 Infamy that faction's Nemesis starts spawning (see the legendary farming article).
• ▸Both tracks are visible in the faction window on the J key.
• ▸Higher difficulties grant more reputation, and the Writ/Mandate boosters accelerate it - the farming procedure lives in the reputation farming article.

The roster: base game, AoM, FG

Which expansion adds which faction - your map of who sells what.

• ▸Base-game permanents: Devil's Crossing, the Rovers, Homestead, and the Black Legion.
• ▸Base-game choices: Act 3 picks between Kymon's Chosen and the Order of Death's Vigil (mutually exclusive), and Act 4 decides whether the Outcast becomes friend or foe.
• ▸AoM (Acts 5-6): Barrowholm (friend-or-foe choice), the Malmouth Resistance, and the Coven of Ugdenbog.
• ▸FG (Act 7): the Cults of Bysmiel, Dreeg, and Solael - all three stay friendly; you simply pick that difficulty's main cult, and nothing turns hostile.
• ▸Principal hostile factions: Aetherials, Chthonians, Cronley's Gang, the Arkovian Undead, and Beasts - with the Aetherial Vanguard added by AoM and the Eldritch Horrors by FG.

What the choice factions actually change

• ▸Only Kymon's Chosen vs the Order of Death's Vigil is truly exclusive: the chosen side befriends you, the rejected side automatically turns hostile, and the available Nemesis changes with it.
• ▸The Outcast and Barrowholm are friend-or-foe choices that never affect your standing with anyone else.
• ▸Factions whose hostility depends on a story choice can have the relationship and accrued value reset by choosing differently on another difficulty (permanently hostile factions' Infamy never decreases).
• ▸FG's three cults never turn on you regardless of the pick - you can even choose a different cult per difficulty and grow all three in parallel.
• ▸How much the exclusive choice's reward differences (gear, augments, blueprints) matter depends on your build - check your build page's gear section when torn.

What you are actually unlocking

• ▸Augments top the list: the classic build-finishing tool for the last few resistance percent, unlocked at Honored/Revered plus a per-augment level requirement (mechanics in the components-and-augments article).
• ▸Blueprints: some component and item recipes are faction-shop exclusives - buy once, learn, and every character in the same mode (Softcore or Hardcore) benefits; the other mode needs its own copy.
• ▸Faction gear and consumables: practical leveling equipment and race-slayer consumables line the shelves.
• ▸Boosters: the Writ at Honored, the Mandate at Revered - the Mandate in particular transforms alt leveling (see the reputation farming article).
• ▸Priorities depend on the build, but the default rule stands: raise the faction that sells the resistance augments you are missing.

1. Grim Dawn Japanese Wiki: Factions — Confirms the two tracks and the J-key faction window, rank thresholds with shop-tier unlocks, the faction roster (base/AoM/FG), the Act 3 exclusive choice (rejected side turning hostile), the Outcast/Barrowholm friend-or-foe choices leaving others unaffected, FG's three never-hostile cults, and the hostile-faction roster.
2. Grim Dawn Japanese Wiki: Glossary (Nemesis) — Confirms Nemesis spawns unlocking at 20,000 Infamy.
3. Official Crate Forum: Grim Dawn v1.2.1.6 + Hotfix — Official patch notes for the verified version.