Dragon Cavalry A cavalry model is treated as a single model, and if the rider is slain the entire model is removed.
Cavalry models use the rider's Leadership characteristic value for all tests that require it.
For Movement the Mount's characteristic is used.
When the cavalry model is attacked the rider's Toughness and Wounds characteristics are used.
Dragon Knights gain +3 to their save
In close combat the rider of a cavalry mount adds the steeds Attack characteristic to his own.
See pg. 17 of 40k Rulebook for more clarifications
Fear If charged by an enemy causing fear, take a psychology check. If passed, fight as normal. If failed, automatically break if outnumbered by charging enemy. If enemy does not outnumber, half the units WS (rounding up) in the first turn of combat and cannot fire overwatch.
If charging enemy unit that causes fear, must take psychology check. If failed, cannot charge and must remain stationary for the turn (but can fire normally).
If hit by a weapon that causes fear it must take a Break test regardless of casualties inflicted by the weapon
