Rogue Trader hands you a character sheet with three layers and then spends forty hours pretending the third one does not exist. Origin, then Archetype at the start, then an Advanced Archetype at level 16, then an Exemplar tier past 36. Most players plan the first layer carefully and arrive at level 16 with no idea what they are choosing between.
Plan backwards. Your Advanced Archetype is the character. The first sixteen levels are a prologue to it.
Momentum is the resource that decides fights
Momentum is party-wide. It builds as you land hits, kill enemies, and act well, and it drains when you take damage or lose companions.
High Momentum unlocks Heroic Acts, which are the swing moves in this game. Low Momentum unlocks Desperate Measures, which are worse but sometimes necessary.
The reason this matters for building a character is that some archetypes generate Momentum far faster than others, and a party built around one of them plays a fundamentally different game. You are not choosing damage. You are choosing how quickly you get to press the button that ends the fight.
Two archetypes are stronger than the rest, and it is not close
Officer does not fight. Officer gives other characters extra turns through Voice of Command, and an extra turn is worth more than any weapon in the game. Stack two Officers and a heavy hitter, and the heavy hitter acts three or four times per round while the enemy acts once.
This is the single most powerful interaction in Rogue Trader. It is also the least intuitive, because the Officer's own damage numbers look pathetic on the character sheet.
Arch-Militant is the damage answer. Its Versatility mechanic stacks bonuses as you use different weapon types in a turn, so a character alternating pistol, blade and grenade builds a multiplier that ordinary weapon damage cannot approach. Pair it with an Officer feeding it turns and encounters stop being encounters.
The other archetypes are perfectly playable. Assassin, Vanguard, Bladedancer, Grand Strategist and Master Tactician all finish the game. None of them break it the way those two do.
Psykers pay for their power in Warp Perils
Psykers get the widest spell list and the only real crowd control worth the name. They also roll on the Warp Perils table, and the results range from mildly annoying to killing your own party.
Biomancy buffs and heals. Telepathy controls. Pyromancy deletes groups. Divination is the quiet strong one, because its buffs stack with everything and it does not push your Warp die as hard.
Run a Psyker if you enjoy managing the risk. Do not run two.
Conviction is a build choice, not just dialogue
Dogmatic, Iconoclast and Heretical are usually described as a morality axis. In practice they gate abilities, companion reactions, and whole chunks of the endgame.
Committing hard to one path unlocks its stronger abilities. Spreading points across all three leaves you with the weak tier of each, which is the most common way players end up feeling underpowered in Act 4 without understanding why.
Pick one early. The game rewards conviction in the literal sense.
Colonies, and how much they actually matter
Your colonies produce resources and raise Profit Factor, which is how you acquire gear rather than buying it outright. Higher Profit Factor means better equipment becomes simply available.
The temptation is to treat colony management as a side activity. It is closer to a gear stat. Neglect it and you will be fighting Act 3 in Act 2 equipment.
Resolve colony events in favour of production early, prestige later.
Difficulty and the honest recommendation
Rogue Trader's combat is generous on normal difficulty and genuinely punishing on the higher settings, and the gap between them is mostly about whether the Officer interaction above is required or optional.
On lower difficulties, play whatever appeals. On Unfair, you need the turn economy, and the party writes itself.
If you are still finding your way through the opening chapters, the Rogue Trader walkthrough covers the critical path.
