TL;DR: the Bottom Line
This game feels more like watching an anime than playing a game. (+) True to the source material. (-) Tedious gameplay.
Can You Play This?
The dialogue is the best aspect to the game, and it’s only in Japanese, so I can’t recommend this to Anglophones. Even if you loved only the combat, alchemy, graphics, you’d be dependent on dialogue to tell you which city or which quarter to visit next.
Reading dialogue quite honestly makes up most of the game. Outside of that the game is walking to where you are told to go, random encounters, and scripted battles.
Characters and Story
The characters are true to their manga and anime (at least Brotherhood; I’ve not watched the other) personas. (We see a bit more immaturity from Mustang than we tend to see in the canonical works, excepting the comical end matter one finds in the manga.)
You can play as Edward, Alphonse, Mustang, Hawkeye, and Armstrong. You can also play as original characters Connie and Martins. NPC’s from the source material include Hughs, Havoc, Gluttony, and Lust.
The story is not bad, I think at least on par with The Sacred Star of Milos. (The latter was in fact not very satisfying, but I find a game of even dull gameplay makes an otherwise mediocre story improved.) Story and the character portrayals are the only good reasons to play this game.
I question whether two points in the game violate cannon. (1) An NPC alchemist manages to make seemingly autonomous and intelligent replicas of humans. (2) Mustang and Hawkeye meet Lust and Gluttony before they would have in the source material.
A great mechanic is the two-timer system, something perhaps not seen in earlier RPG’s: in combat, each character’s time bar fills in accordance with that character’s speed stat, and when the time bar is full, the player can select an action for that character. What’s unusual is that after selecting an action, the time bar turns green and needs to become full again before the chose action is performed. Some actions are “slower” than others, so if you want to throw a punch, you might do so immediately, but if a character wants to perform a costly transmutation (or if a character is simply less skilled at transmutation) then the green time bar may take a long time to fill.
This mechanic adds verisimilitude to RPG combat, and I would like to have seen it spread to many other RPG’s of the time.
You never need to explore, and if you do explore, you won’t find anything except some extra cats (explained below). Talking to NPC’s is not interesting except for the required dialogue.
Your characters do get more HP as time passes (and possibly unlisted stats, but it’s impossible to tell), but random encounters do not contribute to this. Characters’ stats improve whether they are in your party or not. Combat isn’t fun except to get a feel for each of your characters, and that doesn’t take long, so there’s no reason not to run from random encounters unless it turns out that combat gives you money (I haven’t figured out from where the money comes, but I suspect that both it and HP just come automatically as the story progresses).
What’s the use of money? Not much. You can buy medicine, but I prefer to just keep a healer in my party.
Al can collect cats which you may find here and there, and he has one special move which releases a cat from his interior to attack an enemy in battle; this is a nice detail to include that shows a familiarity with Al’s character, but it is not a good gameplay element: finding more cats does not appear to increase your attack power (for all I can tell, and I picked up about eight of them), and the cat attack is pretty weak.
Ed can transmute matter for combat or to open a way to progress through an area.
All cards represent substances. The have a nature (such as metal, plant, earth), a specific name (such as copper, gold, black water), and three numbers (two Arabic numbers and one Roman number). The Roman number indicates the value of the card, capped at 5. Higher levels produce more powerful attacks. The Arabic numbers place constraints on your ability to transmute substances: when you combine two cards, the Arabic numbers of the two cards are added; two cards cannot be combined if either of the Arabic numbers would fall above 7 or below 1.
You can hold 5 cards at a time. Whenever you discard a card or combine two cards, a new level-one card is randomly generated to fill the empty spot.
Ed can to be the strongest combatant if you take time before combat to combine elements to make higher-level substances, but this isn’t stimulating and requires little strategy. If you don’t combine substances outside of combat, Ed’s alchemy attacks will be limited to level-2 cards, and consequently, he will be one of the weaker combatants.
When alchemy is needed to progress through an area, it is always scripted and tedious: you are told what nature and numbers to generate, so you have to sit on the alchemy screen for possibly a long while, discarding cards until you get one that you can use to make exactly the card you need.
If non-combat alchemy had been open-ended and exploratory, it would have provided a good deal of engagement.
All characters besides Ed have a combat transmutation ability, but it does not make use of cards.