Ghasts

Semi-corporeal
Unlike many other undead without bodies, the ghast actually has a tangible form. They not made entirely of essence, rather, from the air of the final breath released in death. They are in fact, made of air and smoke.

Their semi-corporeal nature allows them to handle physical objects and even rely on armor, usually opting to strip them from their own corpse.

While their nature allows them to reform quite easily if disrupted, it also renders them quite weak to physical trauma. Ghasts are often considered the weakest of all undead, even if their permanent destruction is harder than most.