For those looking for a tl;dr version of this review: This is a turn-based RPG, with somewhat snarky dialogue and some fanservice during battles. The style of battle is intuitive and engaging enough to keep things fun.
Let's get into the details now.
So, the gameplay will have you go through chunks of story related dialog, maybe you'll see some scene play out and then you'll be walking around on the map or the dungeon you're supposed to go through. As you walk around, you'll get some random battles, and here's the real meat of the gameplay.
As stated earlier, this is a turn-based RPG. When it's your turn to move, you can either set your character to guard him/herself, use spells (like Super Robot Taisen, these give you power-ups or ways to nerf your opponent), you can switch out if you have more than 5 characters on your team, or you can do a normal attack, choosing what opponent you will strike. Should you choose the normal attack, you'll go into a battle mode where you basically press A to launch a combo, known as a Skill, on your opponent. From there, you can either let the Skill play out, or you can cancel into the next Skill by pressing A again before it finishes. Generally, you want to time your A presses in a way in which the opponent is juggled in the air. As you attack, you can also send in some back-up, pressing Left on the D-pad for a Support Attack (you gotta have more than 4 non-assistant characters on your team), Up for an Assist Attack (this is where the assistant characters come in), or you can press Right for a Chain Attack, which means you switch out one of your characters for another one that can start another round of combos. The amount of Skills one character can do in this battle mode is limited by the COM percentage meter. Every combo will consume a small amount of this bar, and each character can pull off a maximum of 5 Skills in battle. As you attack enemies, you will slowly fill up your Frontier Gauge. With that gauge at 100%, you can use your characters' Overdrives, their most powerful move, which drains 100% of the Frontier Gauge.
Using items can consume some of the COM meter, which is a bit weird to me, but I get it, this is something that's there to make you think about what items you're using. There are items you can buy that can replenish the COM meter, and some characters have spells for that.
In simple battles, you'll just press A a bunch of times to kill off weak enemies. As you go along the story, you'll need to be familiar with the more fine details of combat.
Before jumping right into the battle mode I mentioned, you can, and in major battles, you should, look at your character's spells or special skills to see if you need anything there. The amount of spells a character can do is limited by the Spell Points. Remember, you can find stuff there for healing, buffs, effects on opponents, etc. - You can also use special skills if your character is at a level high enough to have learned such skills. These can come in handy since you don't waste Spell Points with those, and they can be more useful than spells since some of these special skills are attacks.
You can also do some last minute editing of your Skill sets. Your characters have 3 sets of Skills, and you can set them up to have whatever moves are available. The idea here is more than just having a different combination of animations. You can set up combos that spend less COM meter, combos that spend more for more damage, sometimes certain combinations get you a little discount on the amount of COM meter that is spent.
If you want to set that up at your own leisure, there's a Practice mode where you can beat up on a gray robot that will heal every turn. You can use that to test combinations and see how your character's Overdrives work, without having to put yourself at risk in a real battle.
So, there's a lot happening with the combat as it is. That's without getting into the Mentalities of each character that trigger randomly during battle (sometimes with conditions on top of the randomness), the Forced Evasion, the backline characters being able to jump in to defend a player's character, or the accessories that can be added to each character. It's safe to say that the combat is, by far, what this game is banking on, and it's a good gamble to me. I had fun beating up enemies as I went through the story of this game.
The story seems like it'll be crazy, maybe even convoluted due to this being a Super Robot Taisen/Wars title, but it's rather straightforward* here.
Throughout the dungeons, you may notice Wanted signs. These are there just to trigger some powerful opponents that can be battled for the experience, items, etc.
This game also has a little new game+ feature known as the Bonus Dungeon, but you gotta replay the game to even see what that is. I'm still getting through the story at the time I'm posting this. The story has 3 prologue parts, and 17 chapters, so there's a total of 20 parts to the story. The boss battles can go on for a long time, I dare say that sometimes these can get kinda dull. You may get the initial shock of "oh, this guy does a lot of damage" but once you get the idea of how many items you'll need and how many spells you have available to you, you'll be fine. Practice makes perfection. Hell, I'd say you don't have to worry too much about grinding to level up.
Graphically, it's excellent, characters have smooth animations and there are some really cool high quality animations at the start of Overdrives. Some enemies get the old palette swap treatment, but I got no major complaints about the graphics. The backgrounds look fine, and the character designs are all in the good-to-great range for me.
As for the music, there's a lot of tracks here, and none of them are bad. Some of them are remixes of other tracks, but they're generally all good, and I feel like the soundtrack generally captures the mood of combat-filled gameplay just fine.
* - The story of this game takes place months after the previous game. Two new worlds got absorbed into the Endless Frontier, which is a combination of several worlds due to events of the prequel. The two worlds are the Hakoku, which is where the protagonist is from, and the Agrado-Heim, the bad guys. The male protagonist is Aledy Nash, and the female protagonist is Neige Hausen. They get stuck in Hakoku and they are both on a mission to investigate this new world, and along the way, they find allies who help them (some of which need to go back home, like KOS-MOS, Reiji, Xiaomu, etc.), and enemies to fight. A few of those enemies become allies that can help you in battle. Aledy is a wholesome young man, and sometimes humor is made from that. There's also some perverted humor, which is fine for me. This game is for a young audience, after all.
There aren't many flaws to this game, imo, but the story does feel like it kind of overstays its welcome. What I mean by that is that some of the story could have been cut out, but I guess the developers wanted to make this game feel long. You have your usual trope where you beat a boss, but hoho, the boss escapes after the battle and says something about not using full strength. It's not a game killer or anything, but I would have enjoyed this more if the story was shorter. There are also a chunk of characters that I really just don't care for, which adds to my feeling of this game being too long for its own good in some ways.
With all that said, overall, I'd recommend this game, and I just have to say it. Kaguya Nanbu looks so much like Akeno Himejima. That can't be a coincidence, right?