One who is showy but lacking substance or real authority.
dog and pony show
Any presentation or display that is overly contrived or intricate, whi…
all hat and no cattle
Full of big talk but lacking action, power, or substance; pretentious.
talk through one's hat
To speak lacking expertise, authority, or knowledge; to invent or fabr…
hot air
Empty, confused, or exaggerated talk lacking meaning or substance; blu…
all bark and no bite
all hat and no cowboy