Librarius Conclave: The 11th-Edition Space Marines Psyker Detachment

At the start of each battle round you pick ONE Psychic Discipline army-wide; for that round every eligible Adeptus Astartes Psyker — your Librarians and any unit they've joined — gains that discipline's ability, and the discipline also unlocks an extra psychic power. The five disciplines (paraphrased):

• Biomancy — +2" Move on the unit.
• Divination — re-roll a Hit roll of 1 and a Wound roll of 1.
• Pyromancy — +1 AP on the unit's ranged attacks within 12".
• Telekinesis — enemy ranged attacks targeting the unit are -1 Strength.
• Telepathy — the unit's attacks can ignore modifiers to hit rolls.

The key nuance — and a common misconception — is that the discipline is chosen army-wide and rotates each round; individual Librarians don't permanently lock into one. That's what makes the detachment flexible: you re-tune the buff to the game state every round.

Librarius Conclave is unusual: it has no stratagems at all. Instead it trades them for a larger pool of five enhancements, so your customisation comes from what your characters carry rather than from CP you spend in-game. The individual 11th-edition enhancement names and costs weren't published in the sources available at launch, so build from the current pack rather than from older 10th-edition lists (the names circulating from the 10th-edition Grotmas version do not carry over reliably). One discipline-linked trick worth knowing: the Telekinesis discipline can let a buffed unit slip into Strategic Reserves at the end of the opponent's Fight phase and redeploy next turn — an escape-and-reposition tool.

• Librarian — the core enabler; carries the round's discipline to itself and its joined unit. You generally want two or more to buff multiple bricks.
• Librarian in Terminator Armour — a durable psyker that can join an elite Terminator or Gravis brick, putting the discipline on a tough, high-value unit.
• A psyker-led infantry brick — the discipline buffs the whole joined unit, so pair a Librarian with a shooty or durable squad (Pyromancy +1 AP on its guns, Telekinesis -1 Strength incoming, and so on).

Take it as a cheap 1-DP support bolted onto a 2-DP core (an Ironstorm, Anvil, Vanguard or 1st Company list), not as a standalone army. It shines when you already field multiple Librarians and want to tune buffs round by round; it's weak if you run few or no psykers. Because it costs only 1 DP, it slots neatly into the leftover budget of a 2-DP core at a 2,000-point game.

Sample gameplan: deploy two or more Librarians attached to durable or shooty bricks. On a reactive turn pick Telekinesis for the -1 Strength defensive shield (and hold the reserves trick); on your scoring or alpha turn switch to Pyromancy or Divination to spike damage, or Biomancy to grab objectives. Rotate the single army-wide discipline each round to match the game state.