The ninja fight between the fugitive ninja and Fumin bored me a bit. Though the idea of exploding shurikens is amazing, I just hated the fact that the clash between these projectiles is so slow that it made the fight quite dragging. As for the bits that didn't bore me, it's seriously fantastic because it is basically two ninjas using their skills to beat the crap out of each other for a crown that the fugitive ninja is carrying.
The mystery on why she wants the crown and what secret it can possible hold caused Kenta and the rest of the Maskmen to search for her. Thanks to Momoko's knowledge about flowers, Kenta goes to a village where the girl is living. Lucky enough, she is indeed living in that village. After convincing that they are fighting Tube, we now learned more about the history of the Underground Empire. To put it simply, there is a royal family governing the empire before Zeba whose aim is to bring peace in the land and to unite with the ones living underground. So yeah, the empire is not the bad guys but the ones governing it.
The flashback scene showed us Igam's life before meeting Zeba. Based on this scene, Igam had a happy childhood. We saw her play swords and that since the very beginning; he prefers darker clothes over light ones. This scene is one of the first hints we have about Igam's true sex. If there is one thing I learned from watching too much a cartoon involving a “princess waiting for a prince” is that a prince never wears a skirt, he only wears those puff pants or just those regular long cut pants. In addition to that, Igam's hair is longer than your average prince. Those two elements alone gave us fans that are slow in terms of pick up that Igam is a chick and not a dude.
Baraba and Oyobu arrives and tells them that Yu's father is in their hands right now and to save him, they must give the crown to them. Because of Kenta's resolve, they were able to convince Commander Sugata to give him the crown in exchange of the life of Yu's father. I was expecting that the Maskmen will do something awesome to save Yu's father but nope, Yu's father is the one tried to escape from Tube's clutches with his own hands! I mean seriously, the scene made it look like that there is no need for them to give the ransom in the first place!
Out of rage, Yu's father tried to kill the Angler Soldiers all by himself only to end up getting killed in action. It's a seriously emotional scene as you can feel the rage the boils down in Yu's father. He is angry because the Zora Doggler destroyed their opportunity to find out what are Zeba's secrets. As for the giant battle, it is pretty standard so I can't talk much about it aside that the episode didn't feature the formation of the Great Five.