I watched 4 seasons without even playing the game in real life, but I do understand the rules and enjoy the fights though. We get new rule for every season, and this one is no exception. Now we get something so dazzling, which is called "Legion MATE". Okay, just the word choice is so weird, and the word "mate" is being repeated again and again whenever characters talk about Aichi - our forgotten protagonist. Well, I'm sure you will get used to it, just like I did. Please note that this anime, or the whole series, is there for the purpose of promoting cardgame and sellingdesks in real life. People watch this mostly to know the power of cards instead of reading plain Wikipedia. Thus, the plot of the anime is not something splendid or awesome, it happens to show the cards. Although I'm saying that, I actually enjoy its simple plot. I love how they shift Kai to be protagonist now to make him gain more development, especially after season 3, where he has many problems. His problems is being showed here as well as an element to build up his character. Maybe this season is actually the first time we see him acts like a leader, a friend, and a "mate" of Aichi. We see him struggle to overcome his sin in the previous season, and his interaction with others. However, other characters like Misaki and Kamui are being overshadowed.

The Quatre Knights is not really an interesting gang, but the director at least cares to create the background for every member, though most of them don't make sense at all (Anyway, turning off your brain is the best way to enjoy this anime). As Cardfight on Moon is not magical enough, we have them fighting by Ice and Fire Power like they just come out from Sailor Moon. I don't think it's necessary at all but it doesn't hurt anyone, I guess. We also have a little plot twist with Serra - one of the Knights and Leon and Ren, which I think is a step-up from previous season that I find it rather interesting.

The art is decent enough for a long series like this, though sometime they make such silly mistake like the cards in Damage Zone change magically in the next scene. Some of the animation appears to be great when the characters summon their Ace Cards. The voice acting is great, and their screams are marvelous, I should say.

The Openings don't appeal much to me, but I like the second ending, it gives me warmth. I kind of sympathize with Aichi right now. The OST is plain boring, well, I didn't expect anything from its music anyway. Hopefully I can hear "Believe in my existence" as insert song once again, maybe in the last fight that probably would happen between Kai and Aichi.