The Icy Cube is an Emblem Heartless that is found in Kingdom Hearts II and Kingdom Hearts 358/2 Days. It resembles a large ice cube and is controlled by the Blizzard Lord. Whenever Blizzagun is used on the Blizzard Lord, it explodes into a group of Icy Cubes. The Icy Cube's counterpart is the Fiery Globe.
The Icy Cube's body is blue and spherical, with two featureless legs sprouting out of its bottom and a twisted antenna coming out of the top of its head. Its Heartless emblem is present on its forehead between its two glowing, yellow eyes. The Heartless's body is almost entirely frozen in a block of ice, save for the tips of its legs and antenna. Icy Cubes are very small Heartless.
The Icy Cube's name is a reference to its shape and attribute, as well as real-world ice cubes. It is also a contrast to the Fiery Globe's name.
Kingdom Hearts II
Despite its icy appearance, the Icy Cube is not actually especially weak to Fire magic, though it is immune to Blizzard and resistant to Thunder. Despite this, Fire can still be a good way to clear out crowds of Icy Cubes during the Blizzard Lord fight, otherwise simple physical combos will be sufficient as they have little in the way of defense and lack any complex attack patterns.
Kingdom Hearts 358/2 Days
Icy Cubes can be dangerous up close due to their capability of freezing Roxas, so physical combos are not advised. Instead, Fire magic should be prioritized as the Icy Cube has a massive weakness to it, being eliminated with as little as one cast of Fire magic. As long as distance is kept and Fire magic is used, Icy Cubes will not pose a threat.