Gunzhard wrote:
Maybe you don't care but the Knights are never piloted by Space Marines in the fluff.

The are very separate from Marines, like an Admech Dunecrawler or SoB Immolator... moreso because they survived the Age of Strife pretty much unchanged and unharmed while the rest of mankind went to hell. The old feudal hierarchy of knight houses has therefor pretty much remained unchanged since before the Imperium was born.

Knightly houses, have been known however, to pledge themselves to certain marine chapters and carry campaign banners and chapter heraldry on their armor.

I did mine as House Hawkshroud, pledged to the Blood Angels: http://atticwars40k.blogspot.com/2016/05/imperial-knight-house-hawkshroud.html

Now if you don't care about the fluff, then you aren't limited to the schemes in the codex either.

 Gunzhard wrote:
Maybe you don't care but the Knights are never piloted by Space Marines in the fluff.

The are very separate from Marines, like an Admech Dunecrawler or SoB Immolator... moreso because they survived the Age of Strife pretty much unchanged and unharmed while the rest of mankind went to hell. The old feudal hierarchy of knight houses has therefor pretty much remained unchanged since before the Imperium was born.

Knightly houses, have been known however, to pledge themselves to certain marine chapters and carry campaign banners and chapter heraldry on their armor.

I did mine as House Hawkshroud, pledged to the Blood Angels: http://atticwars40k.blogspot.com/2016/05/imperial-knight-house-hawkshroud.html

Now if you don't care about the fluff, then you aren't limited to the schemes in the codex either.

 Flugel Meister wrote:
Have decided to go with a traditional looking BA colour scheme for my first Knight. However, I've removed half the face armour and painted it gold in memory of Erasmus Tycho. The Knight will also be named Erasmus.

Fluff-wise: From Tycho's actions on Armageddon, when he was Death Company and died against the Orks, provided enough time for this particular Knight from House Terryn to re-arm when the Orks were sure to overrun and kill the crew, rendering the knight useless in the campaign.

Tycho's charge with the Death Company delayed that, allowing the crew to get the knight ready and then support the advance. As a mark of respect, the house allowed the crew to paint the Knight in BA colours and modify the face armour, while retaining House Terryn markings in addition to BA insignia.