Granbelm is your latest creatively bankrupt seasonal anime featuring bright haired anime girls with tragic backstories in chibi mecha. In essence, this work, by the director of the infamous Re:Zero, is an isekai (sort of) magical girl mecha battle royale where the last mage standing will get the mysterious macguffin that grants wishes. We are introduced to the protagonist Mangetsu who is your usual "do-no-wrong" character who mysteriously ends up in the Magical World despite only those with mage ancestry being able to, and totally does not have a super power lying dormant within her due to such ancestry with an ancient powerful mage. Mangetsu becomes aware she does not have a personality so she instead joins in the battle royale to help Shingetsu fulfill her wish.
In this world, magic existed once back in ancient civilization until it was sealed by a circle of mages who sacrificed their lives to do so, but apparently they didn't do such a good job since there are still magic users on Earth and they are able to use magic powers, in and out of the separate world. Despite this magic originally being used by the oldest civilizations of Europe and West Asia, all of the current magic users happen to be pubescent Japanese girls. It would've been much more interesting if it used Japanese history or folklore as to explain this, but alas the writers must've realized that would take effort.
Mecha battles within the magic world consist of characters winning based on how many times they say "envision" or which character remembers their backstory and motivations the hardest. There are also other asspulls such as characters randomly triggering super powers that allow them to win based on how angry they are or random magic powers that weren't ever used prior. The constant back and forth rivalry of Shingetsu and Anna becomes tiring when you realize Shingetsu is just a Mary Sue and Anna is your designated character to hate because she's a pompous yandere that will likely just stop being that and become a good person in the future. The latest episode certainly points to this direction yet lacks the nuance to actually pull it off because we were never given a reason to care about anything happening besides surface level character motivation.
Of course conveniently, these mecha called "ARMANOX" are the "reflection of the user's soul" or some drivel like that as to explain why characters don't ever have to be any good at using the mecha and can just rely on the writers to decide how it should all go.
The wish granting macguffin of this magical world battle royale only involves the most basic motivations when it comes to character's reasons for obtaining it. It's not like I was expecting something on the level of the movie Stalker when it comes to philosophy surrounding such a wish granting device but it's like they didn't even want to try.
There's also some conflict between Suishou and uhh the other white haired girl over her sister which is so poorly conveyed that it's laughable. At least the creators were smart enough to realize how boring and forgettable the characters were so they color coded them.
Speaking of that, the artstyle and design is ultimately "whatever." There's a lot of "same face" which also explains the color coding and they over utilize the exaggerated faces for the sake of portraying someone as crazy or mad. Also the mecha have awful designs that look like toys more than anything dangerous.
If someone looks at this as a "dark magical girl" show and begins referencing Madoka then that's when you know it's bad. If you want "dark magical girl" just watch Utena. If you want mecha, watch Gundam. If you want an anime with a cast of bright haired anime girls then go watch whatever waifubait show is on this season. Don't watch this, it's a complete waste of time.