The Wolf Knight's Greatshield is the spiritual successor of the Greatshield of Artorias, though whether is it exactly the same shield is unknown. It has decent stability, and is the third lightest greatshield in the game. It is also the greatest stability shield that can allow you to perform the skill of the main hand weapon. On top of that, wielding it boosts your resistance to many status effects.
Its main weakness is its lack of lightning defense, and if you want good elemental defenses on your greatshield, you might want to look elsewhere.
Upgrades with Twinkling Titanite.