Because Igor is disappointed with the music that the music-themed Ganma is creating, he of course, goes on a slump and by sheer coincidence, meets Cubi and Kanon. Because the both of them only want to do their art, they ended up bonding, which lead to Igor discovering it. There's nothing much to say about it since all we got is two Ganma not fighting. Thankfully, something interesting happened in the form of Javert saving them from Igor's attack. This is just him repaying Onari's kindness from the previous episode, making this scene really meaningful.
Now to the more important stuff about this episode, for starters, let's talk about what happens after the death of the Emperor. Alain was dead silent, felt like his entire body stopped working that's why he's just kneeling there for at least 80% of the entire episode. Seriously, Takeru is just dragging his body around until he snaps later in the episode thanks to Makoto and Adel. It didn't help that when they met Alia in the episode, we barely got a reaction coming from her in regards to her father's death! To put it simply, I barely felt the impact of the Emperor's death since it feels like it happened and they just moved on with their lives.
What happens next is really interesting as this is the first time we saw all three Riders transforming together in battle as a team. It's a really great sight, only to be ruined by Ghost Grateful Damashii getting frozen due to the influence of the Ganmaizers. Because of this, what we got is a scene of Specter and Necrom teaming up, and it looks really good. Seriously, this is the kind of team-up that I want to see, not Necrom ordering Specter around like his puppet. This team-up was short lived because the enemy Ganmaizer is so powerful, it didn't help that Ghost is down for the most part of the fight!
The closest thing that we got for build up in this episode is just Makoto standing up and deciding to use the Deep Specter Eyecon. The previous episode only warned us the dangers of its power, but we never saw how dangerous this new power is at the end of the episode. What we got is just Makoto struggling in some kind of energy smoke and agreeing to the terms and conditions of the new power. That's it, no explanation of its dangers. What happens next after this scene is something that the director felt like he is obliged to do so that Bandai can sell new toys.
The episode ends and we learned that Cubi left with the music-themed Ganma because both of them are in a slump and want a change of pace. Oh, and Alain finally calls Makoto, Makoto and not Specter. That's a nice piece of character development in my opinion. Also, they continue on building some stuff regarding the Ganmaizer but since it's all mysterious and stuff, I can't figure out what's going on. What I got is that the Ganmaizer that was summoned in this episode returned to its original state.