This article is about a/an set of villains in Hikari Sentai Maskman.
Underground Empire Tube
Led by: Earth Emperor Zeba
and later by: Princess Ial
Generals and other Notable Members: Igam, Anagmas, Baraba, Oyobu, Fumin, Okelampa
Monster Types: Earth Imperial Beasts Doggler
Base: Underground Castle
Grunts/Footsoldiers: Ungler Soldiers
Battled: Maskmen
Teamed up with: Thief Knight Kiros
Chronological/Production Order
Reconstructive Experiment Empire Mess
Armed Brain Army Volt

The Underground Empire Tube (地底帝国チューブ Chitei Teikoku Chūbu) is an underground kingdom bent on conquering the surface world.


Originally, Tube was peaceful underground empire ruled by the Igam family who slain a dangerous monster terrorizing their realm called Lethal Doggler. However, the Doggler had a son who infiltrated the Igam kingdom as the usurper Zeba who corrupts the land into a violent kingdom where strength rules all while enslaving the underground humans. However, Zeba learns that his downfall will be caused by the Igam family's two surviving members, twin sisters Ial and Igam, and decided to keep the two apart to maintain his dominion as he turns his attention to the surface world and used the former a spy. But her falling in love with Takeru and attempt of warning him of the invasion gave him a reason to permanently separate the twins by sealing Ial in ice while Igam grew to hate her sister for dishonoring them and takes out her rage on Takeru as he joins the Maskmen to fend off Tube's forces.

But due to Thief Knight Kiros, Ial is released and, despite his attempts to keep his true identity hidden, Zeba is exposed as Lethal Doggler the 2nd as he has the Underground Palace taken to the surface to encase the Earth under his Dark Aura. But with Ial and Igam's restored sisterly bonds empowering them, the Maskmen destroy Zeba with Ial taking her sister's place in restoring the Igam Kingdom.


Ungler Soldiers

The black skinned foot soldiers with vines covering their faces. Their names are derived from "underground."