Character Shilling: Episode 37 and 38 spent some time presenting us with Hikaru's sudden genius in regards to rescues, with both Eiji and Kyousuke, both of whom are well acquainted with his personality suddenly labelling him as the best choice for next Captain because he figures stuff out a couple times. This is ignoring the fact that Hikaru would be hopeless at all other Captain duties, not to mention being the youngest, the the rookie, and very reckless. While Hikaru might make good field calls, the show ignores the fact that the other candidate, Kyousuke himself, is far better at the administrative and core aspects of leading in favour of pushing the main character as the leader's successor.
Ending Fatigue: The show follows a standard Sorting Algorithm of Evil up until the climatic death of Maaen in episode 38. It then becomes clear that, either for creative or budgetary reasons, the show did not have a new villain or gimmick to fill the gap until Batsu's introduction in episode 49, so it just Handwaves Maaen back into existence and brings back a parade of the previous villain gimmicks.
Fridge Logic - At the end of episode 38, despite the saw portion of Drill being excluded from the ultimate combination, the damaged remains of Drill show it attached.