"Horde" and "hoard" are not the same thing. While they both generally refer to a quantity of objects, they have different applications. "Hoard" refers to inanimate objects, while "horde" refers to creatures. In other words, just to keep this Skyrim-centered to avoid getting moved or locked, if you fight your way through a bunch of bandits and take their stash of potions, then you have fought through a horde of bandits and taken their hoard of potions.
Got it? The Grammar Nazi is here to serve.