Centaur Warrunner is a tanky melee strength hero who is most often played as either a support hero or an offlane initiator.
He deals tremendous short range AoE magic damage, at the cost of his own health, but his own innate tankiness ensures this deals far more damage to his opponents than himself. His AoE stun and global team-based ultimate also give him good team-based utility.
Skills
Hoof Stomp is usually skilled first (for safety) and maxed second.
Double Edge is maxed first and is your main source of damage.
Return is maxed last but an early point is very useful in the offlane to dissuade harass.
Stampede is always skilled (levels 6, 11 and 16).
Items
Starting Items: Tangos, Healing Salve, Ring of Protection, 3x Iron Branches.
Early Game: Tranquil Boots, Magic Wand.
Core Items: Blink Dagger, Hood of Defiance.
Luxury Items: Pipe of Insight, Crimson Guard, Blade Mail, Heart of Tarrasque, Drums of Endurance, Heaven's Halberd, Shiva's Guard.
Situational Items: Vanguard (early game health), Boots of Travel (late game), Necronomicon (pushing line-up), Vladmir's Offering (melee cores), Assault Cuirass (if no one else gets it late game).