First things first. My "reviews" system is explained on a blog entry. Which can be found through my profile.
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So what even happened? I did enjoy the first season a lot. Whilst this one just bored me to death and thus dropped. The whole season (the whole 13 episodes I watched) felt as a filler season. Basically plot about Beet and his team crashing into city and camping there for the rest of the anime. Random boring villains get sent to attack the city and Beet team defends. Also the main enemy is also quite boring. I quickly skipped to the last episodes to see whats going on and yeah...indeed it's all about the warden.
Point being, fights were boring, villains and characters felt useless. And the whole Beet training the tengeki was also quite a boring presentation.
I'm not sure what happened here, but one thing for sure. In comparison of the first season, the second one is utter letdown and boredom.