nouveau chevalier impérial

The codex is a mash-up of the Knight Companion and a very well re-written Codex (including fluff).

All five Knight variants are Lords of War (LoW).  Also, if you take the Primary Detachment ALL Knights get Objective Secured.

A Primary "Household Detachment" is consisted of at least 3 LoW with 2 optional LoW.
  Command Benefits - Knight Commander, Lord Baron, Objective Secured

An Allied "Oathsworn Detachment" is consisted of at least 1 LoW with 2 optional LoW
  Comman Benefits - None

The Knightly ranks system as we knew it is now gone.  You no longer have the option of rolling for better stats, it's handled in a much more static but robust way.  In a Household Detachment the Warlord gains the following two rules for free, along with Objective secured for all members of the Detachment;

Lord Baron - This is now the Warlord rank for a Household Detachment.
 +1 to Weapon Skill
 +1 to Ballistic Skill
 No bonus to Ion Shield
 Gains "Character" unit type so can make/accept challenges
 May purchase Heirloom items

Knight Commander
 Lord Baron gains re-roll to Hit during a challenge

All Knight variants share the same stats profile but vary in cost, the costs shown below are base costs without upgrades

Errant - 370
Paladin - 375
Gallant - 325  (Weapons are not specialist so grant +1 attack for 2 CCW's)
Crusader - 425
Warden - 375

There are 5 Formations in total, i'll give basic info on these

Exalted Court - 5 Knights (any type)
All Lord Barons, all have "Character" added tp unit type
1 can must upgraded for free to High King/Princeps
High King gains +2 BS/WS and +1 to Ion Shield

Baronial Court - 3-5 Knights (any type)
One Knight is upgraded to Lord Baron
Ionic Shieldwall - Knights from this formation within 6" of another Knight from the formation gain +1 to front facing Ion Shields
Knightly Vassals - Knights within 12" of the Lord Baron (if he is your warlord) can fire Overwatch (!!!!!!!!!!!) despite being super-heavy walkers and gain Counter-Attack

Tripartite Lance - Warden, Crusader, Gallant
Whilst the live the Knights in the formation are part of a single unit and must act accordingly.  also, whilst alive, each Knight provides the following bonuses
Warden - All shooting attacks made by Formation count enemy cover as 1 less (ie 4+ becomes 5+)
Gallant - Models make D3 Hammer of Wrath attacks
Crusader - All template weapons in formation gain Twin-linked

Gallant Lance - 3 Gallant
Gain Crusader and Rage
Full Tilt - Re-roll failed charge ranges

Skyreaper Lance - 3 Knights of any type
All MUST have Icarus Array
Re-roll to wound against Flying MC/GMC
Re-roll failed armour pen rolls, re-roll glances to get a better result (must accept 2nd result)


Warlord Traits
Warlord and friendly Knights within 12" add +1 to run/charge range
Nominate a weapon to become master-crafted, cannot be an heirloom item
Re-roll to hit in combat if he charges
Warlord +D3 friendly Knights gain Outflank
Re-roll failed Ion saves of a 1
+1 attack

Heirlooms
Friendly Armies of the Imperium units within 12" must re-roll failed Morale, Pinning and Fear tests
Gain Rampage
It Will Not Die
Master-crafted Thunderstirke
S;D AP1  Chainsword that can re-roll to hit rolls of 1
Sanctuary.  Ion shield that grants a 6+inv to facings not covered by Ion shield