Chivalry

Chivalry is askill introduced in Fire Emblem Fates. It is the Personal Skill of Xander.

Fire Emblem Fates
If Xander attacks an enemy whose HP is at maximum, he will deal an additional 2 damage to his attack and will receive 2 less damage. If Xander double attacks, the second attack will retain the bonus damage and will retain the bonus damaged shaved if counter attacked. It will not reduce damage received from counter related skills.

Trivia
Chivalry is the inverse of Pragmatic, Leo's personal skill, as Chivalry receives its boost when Xander faces an enemy whose HP is at maximum, while Pragmatic does if Leo faces an enemy whose HP is not at maximum.