My turn then.
Disclaimer: Remember that this is a person's opinion about cardfight characters. LARGE WALL OF TEXT YOU HAVE BEEN WARNED!!!!! That's the main reason for the spoiler tags.
Spoiler
I could never really settle on just one character ether both unit and the characters playing those beautiful units. Though I mostly like the females cast. Though a lot of males stood out as well. I'll start with the female cast. Disclaimer: I know that Cardfight Units don't have genders. But I will separate them as such anyway.
Unit wise Most of the females are amazingly well drawn and animated. Even units that I normaly don't like in the card game for reasons I will not get into, I can enjoy how beautiful the art is in the animation. Sphere Magus was one of the most beautiful of the all as Well as Tsukuyomi in all her beautiful forms. Even Amaterasu in both her forms, a card I do not like much in the card game, was really beautiful anime wise only to name a few from my favorite clan though I like all of them except for 1. In other clans The "Amon" girls, Edel Rose, Most of the NN girls, Ashlei, The entire cast of Bermuda, hell even the cheer girls from Spike and the lovely Pale Moon Circus Girls. They all mostly stood out to me because of how well done it was brought to the screen. Each one had a charm that another one did not have.
As for the female characters I like them all in someway but 3 stand out the most. Emi hands down is the best female character for the almost the entire series. She's cute, adoreable and most fitting of her character. I kinda wish they did more with Emi. She feels more like a adult then a 10 year old as well. Misaki was also enjoyable in season 1-2. She brought out the best out of my favorite units. Oracle Think Tank. I didn't really like it when she changed to Genesis in season 3 but even then she was still fun to watch and she used it well even though it just wasn't as fun. The last favorite character from female cast that I hope will see some more action sometime soon is Maki. Even though she was reversed for most of the season 3 plot. Learning her backstory made me feel bad for her. It was even a surprise finding out she was reversed. It's sad her plot line was so short. Because she was one of the few reverse fighters that was enjoyable to see what would happen next. She was the best season 3 female character to me which I did not expect to say especially after the fact Emi put such a fantastic show with Labrador. She was seen in season 4 once so maybe we'll see more of her at some point.
Now for the Male cast.
Starting with favorite male unit is outright Blaster Blade. He brought us together into vanguard someway or another. In episode 1 he was the main reason I continued watching cardfight vanguard series at all. Then comes Silent Tom a few episodes later. A ghost in a suit with a lady ghost around him and has guns in his fingertips. Win! Then came Gancelot on his beautiful white Pegasus ready to swing his sword at anything his 9000 power self could do. Then Amon shows his dark demon power. You know I could go on for days about a lot of the male units but these are some of the early few that kept it going. Anime male Blaus, Raizers, Spikes to name a few more that I also enjoyed and of course OTT units.
Now for the Male Characters and again 3 of them stand out the most.
Kamui is one of the best male characters. Though a lot of people find him annoying or whatever bad people say about him in this day and age. That's part biggest charm. He cares about his friends. Stays positive and is always learning from his mistakes. He even shown how far he's come in season 3 when he saved Emi from Rekka. It's too bad he ended up reversed but even then he still manages to keep that charm during that last bit of the season. I hope he will be used the the fullest effect in season 4 and from what I've seen so far I'm not disappointed. Koutei is next with amazing character. He stays cool and collective and always seems to have a good strategy except when around Yuri but that's another story. He brought out some of the best moments in the anime in it's entirely. Especially in season 2 and 3. Each moment with him was much stronger then the next. I wish they would use him a bit more as well. Finally Leon. He brought back a dieing clan back to life and is one of the only few to be able to use it. His caring character is his biggest trait. Although he was a villain in season 2 his heart was always about saving his people he cared for. If that wasn't enough Leon is the true winner of the season 2 final battle vs Aichi. (only true if you consider the animation error that bushi did not account for of course)
and thats it.
Also I like all character form Foo Fighters Brilliant Stars, whoops did I say Foo.. I mean Team Asteroid Brilliant Stars because of their blinks :3
Andyes I want more screen time for them!
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