The Knights of the Questoris Familia are making a triumphant return to the battlefields of the Horus Heresy in the new edition. Here’s Baron Al of House Playtestoris* to explain more.

The Knights of the Questoris Familia are a small, aggressive army that likes to push towards enemy-held objectives. Both the Questoris and Cerastus chassis of Knight have the Vanguard (X) special rule, allowing them to score victory points for destroying or routing enemy units holding objectives.
This can of course put them in hazardous positions, but as most Knights have good frontal armour, it means you are immune to small-arms fire when well positioned. Knights are not invincible however, and they can be brought crashing down if you’re not aware of their surroundings.
Household Paradigms
The way you build a Questoris Familia army has changed. No longer do you have to take Armigers to unlock the larger Knights, so players have more freedom to include all their favourite patterns.
When building a list you pick a Household type: Imperialis, Mechanicum or Mendicant. Each has a unique set of bonuses, including a Tactica, a Vow and an Advanced Reaction.

Household hierarchy
The second thing to note is that Knights have a unique Primary Detachment which is used instead of the Crusade Primary Detachment. It doesn’t allow Allies, but it does permit more Lords of War choices, while each slot is a Prime slot, allowing every Knight to choose a Unique Prime Advantage.
There are plenty of these to choose from, representing the various ranks within the households. For example, Lord Scion allows a Knight to make two repair rolls at the end of their turn. You must be wary of Tactical Statuses, which can hinder your Knights significantly, so additional ways to recover from them are very useful.
Some of the ranks can unlock unique Detachments for the army. The Lord Scion can access the Yeomanry Mesnie which allows you to take Solar Auxilia units. This is a brilliant way to add flexibility and uniqueness to your lists.

YEOMANRY MESNIE
[Additional Detachment]
When the Lord Scion Household Rank Prime Advantage is selected for a Unit in an Army, then the Player may choose to add one Yeomanry Mesnie Additional Detachment to the Army.
Units selected to fill Slots in this Detachment must be selected from the Solar Auxilia Army List found in Liber Auxilia or the Imperialis Militia Army List (in any combination). Models selected as part of this Detachment replace their Solar Auxilia or Imperialis Militia Trait with the [Questoris Familia] Faction Trait.
The Preceptor rank is another decent choice, which gives the Knight the Battlesmith (2) special rule and counts as Intelligence 8 when making Repair tests for this special rule. This allows your Knight to repair or remove Tactical Status from itself and other nearby Knights. This rank also unlocks the Automata Talon, which allows you to include bonded Mechanicum units including Castellax Automata.

AUTOMATA TALON
[Additional Detachment]
When the Preceptor Household Rank Prime Advantage is selected for a Unit in an Army, then the Player may choose to add one Automata Talon Additional Detachment to the Army.
Elites Slots in this Detachment may only be used to select Domitar Battle Maniple Units, Support Slots in this Detachment may only be used to select Castellax Battle Maniple Units, Recon Slots in this Detachment may only be used to select Vorax Attack Maniple Units, and Fast Attack Slots in this Detachment may only be used to select Vultarax Stratos Squadron Units, each selected from Liber Mechanicum. Models selected as part of this Detachment replace their Cybernetica Trait with the [Questoris Familia] Faction Trait.
Take a vow
When selecting a Knight in a Knight army, you can also select a Vow for each one. These will reward you with additional Victory Points when you fulfill their specific requirements. There are four base vows, each corresponding to a different secondary objective in the Core Mission Pack, and each of the different households has an additional Vow to reward you with Victory Points in new ways. Be wary though, because if you accidentally fulfil the conditions with a different Knight, those bonus Victory Points can be lost.

VOW OF BELLIGERENCE
Shorn from their Houses, freeblade knights hunger to acquire a fame and prowess which rivals their one-time peers, the Vow of Belligerence swearing them – often rashly – to be the first warrior to break the foe’s lines.
If a Model with this Questoris Vow is part of the first Combat in a Battle for which the Controlling Player is declared the winner, the Controlling Player gains 2 Victory Points.
Standout units
There are quite a few exciting units in the Knights army list. First and foremost is the Cerastus Knight Atrapos. It's expensive at 600 points, but it’s tough, quick and can deal a large amount of damage with both shooting attacks and in melee with its Atrapos phasecutter which has a Damage characteristic of six (which can increase to 12 if it remains stationary before shooting!)

Another good choice is the standard Knight Questoris. This is the cheapest of the larger Knights and the most versatile. It has a wide choice of weapons and allows you to specialise the Knight to your playstyle. In particular I like the thermal cannon, reaper chainsword and twin Icarus autocannon, creating a great all-rounder that can deal with a multitude of targets.

My third choice is the Acastus Knight Asterius. The fearsome conversion beam desolator array can dominate the battlefield and help direct enemy units into killing zones as they move to avoid its massive arc of fire or face obliteration.
Thanks Al! The Knights might seem large enough, but they’re still dwarfed by the Titans that they share a Liber with. We’ll have more on these epic god-engines and their special Engine Kill mission soon.
* This is not a real house.