Rare Heartless = Bulky Vendor.

Found in:
Lands of Dragons (L35), 760 HP
Beast’s Castle (L36), 770 HP
Olympus Coliseum (L39), 820 HP
Agrabah (L40), 840 HP
Halloween Town (L41), 860 HP

Depending on the Reaction Command used on it, it will either drop a
Bright Shard, Stone, Gem, or Crystal, and a small chance of a Orichalcum. After you obtain all the Orichalcums in the game, this is the only way to obtain more. This DOES NOT DROP ORICHALCUM+.

Capsule Prize (HP between 75-100%)
Drops Bright Shard (100%), Orichalcum (8%)

Rare Capsule (HP between 74-50%)
Drops Bright Stone (100%), Orichalcum (10%)

Limited Capsule (HP between 49-25%)
Drops Bright Shard (100%), Orichalcum (12%)

Prime Capsule (HP between 24-1%)
Drops Bright Shard (100%), Orichalcum (16%)