Problem was with the power creep, or escalation of the conflicts, and the human being unable to fight because of their setting (they were supposed to be weaker than animals without technology or weapons), so they had to introduce new animals to take on the enemies.Fun series. Raiku might have bitten off a bit too much for the plot of the series and it might have had too many characters, as I stopped seeing my favorite characters as a result, but I enjoyed my time with it.