Successfully complete The Black Gates level under the hard difficulty setting in Good mode to unlock Haldir, the elven Captain of Lothlorien.

His stats and equipment are:

HP: 20
SP: 8
Move: 4
Attack: 6
Range: 6
Morale: Brave
Leadership: Average (0-3)
Light Armor (+2HP)
Elven Hood (+2HP, Grands Stealth Skill Level 2)
Elven Cloak (Defense Bonus; Damage -1)
Skill: Keen Eyes