UPDATE: 2014Oct29
I'm dropping my review a full two points, from 9 initially to 7.
This review is on the XBOX ONE. It seems last-gen players are really getting shafted in the gameplay compared to new-gen. Last year FIFA14 was WAY worse on the Xbox360 than it was on the Xbox One (though it still sucked), and I think from the reviews I'm reading from other people, FIFA15 must be the same in the way it handles last-gen gameplay.
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Updated information 2014Oct29 (mostly co-op related)
Many of the improvements I had initially reported are really only seen for the single-player experience (OFFLINE mind you)
For the co-op experience, all of the issues present in FIFA14 are still there in FIFA15. After dozens of games on the couch, my friend and I have concluded that AGAIN, just like in FIFA14, the game appears to drop your player's stats a full 10 points each time you raise the difficulty. The harder you make the game, the stupider your players get. It is extremely frustrating to be able to do so well in single-player, only to find ridiculous idiocy taking over when adding a 2nd player. This applies to Ultimate Team, Manager Career and Player Career, whenever you do not lock to a single player. Fortunately, at least, you have tweaks in Career mode, but none of these are available in Ultimate Team
All of these issues become worse and worse the higher you set the difficulty. On Legendary your teammates become morons while the other team become gods.
--Unowned balls rolling right in front of players and having them fail to grab it.
--Defenders failing to engage for any reason
--Throw-ins failing to find a player
--The game not allowing a teammate to receive the ball during manual passing that doesn't really go to any player.
--AI being able to tackle from behind with consistent success, while we get fouled every time we try.
--Ridiculous counterattacks that often lead to scores
--Unable to outrun defenders with extremely fast strikers
--Opposing team able to dribble around slide tackles consistently.
--Extremely difficult to dribble around players once you start playing Professional or higher difficulties.
--Goalies being unable to do a ground pass during a goal kick without giving the ball to a teammate and then getting scored on.
--Etc
My friend and I love playing Couch co-op, but these issues lead to extreme frustration and anger, to the point we don't play co-op any more.
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Original review
I've played FIFA since 2009. I can say that FIFA14 was the first game I ever sold back to gamestop (after giving EA 3 months to fix it, but only got minor fixes)
For those who played FIFA14 on World Class or Legendary difficulty you know what I/m talking about. It felt like the game subtracted 10 points from all stats on your players, and added 10 points to the AI players. It was NOT FUN to play FIFA14.
Here are some things I've noticed they've FIXED (playing UT and solo career)
-Deflections actually go in logical directions now! The 99% deflection-to-the-opponent has been fixed! Can't tell you how awesome this is.
-AI Players now try to move to open spaces to receive throw-ins, but you can switch the receiver of the throw-in and move to an open space yourself.
-Corners actually have some strategy to them! You can select (with the D-pad) what kind of runs you want your offense to do during corners.
-AI doesn't do long lobbed passes to win in the 90th minute every single game
-Dribbling when sprinting is 1000x better, and you are able to stop almost on a dime and turn. Even better is the fact that you don't seem to lose possession of the ball 1 second before you visually lose possession, and it feels like you can actually DO something about incoming tackles (not always, but in most cases vastly improved)
-Can finally create spaces to exploit. Moving the ball into the box is not only possible, if you're patient, but often yields a shot on goal.
-Headers are much harder to pull off inside the box, but that's as it should be. A header in the back of the net is oh so sweet now, because it's so uncommon.
-Your AI teammates actually try, and sometimes succeed, in tackling the ball from an opponent. This is an incredible improvement over FIFA14 where teammates would just watch the ball roll right in front of them without doing anything (which got much worse the higher difficulty you played on)
-AI defenders no longer seem to trip over each other and are far more effective inside the box
-New Team management and player tactics are AWESOME
-Scoring at lower difficulties is finally easy
-There's a new "beginner" difficulty which is even easier than Amateur.
-All of the acrobatic clearances by defenders are gone. Finally!
-Most defenders don't do a 180 and boot the ball way downfield when kicking the ball out of bounds. They still boot it way up in the air (rather than tap it out of bounds like real defenders do), and they still do some twisting. But it's way better than FIFA14.
-The AI will actually put way more pressure offensively late in the game when they are down by one goal. This is fantastic and realistic. The commentators will even notice this.
-Highlight/pause reel is definitely better.
-Can now choose what news to share with your friends among all the various activities you've completed (skill games, winning a season, etc). You can even thumb-up or comment on other friend's news.
-You can share your UT team with friends so they can see what you've got.
-You can create your own tournaments, though I haven't done this yet.
-Player ratings during solo careers is less intrusive and seems a bit more lenient.
Some things still are NOT IMPROVED:
-Solo career still has the same accomplishments for growing your Pro as 14. Suckage.
-Some fouls are still called against the possessor for ridiculous reasons
-Still can't have multiple copies of the same player in your Club. I'm sure there's a good reason for this, but I also find it stupid.
-Absolutely hate the fact that the "bonus" for the "Ultimate Team" edition is 40 packs over 40 weeks. In no other retail situation I can think of do you have to wait to get a product you purchased. You save a ton of money on packs, but have to wait almost a year to get all of them.
-Player-Manager career is still gone and probably will never come back.
-You still can't have your couch buddy get EA xp the same time as you. Only in online co-op can you both get XP.
-Manual passing still has instances (50%) where the game cannot detect who the receiver is supposed to be and doesn't allow your teammate to receive it.
Some things are WORSE:
-Commentators commenting on players (new arrivals, out of form, etc) used to highlight the player they were talking about (by showing a picture of the player in the top-left corner). Now you have no idea who they are talking about.
-UT: Can't trade cards with your friends any more. They supposedly did this to stop the gold sellers but now I have to get really creative to try to sell cards to my friends. Stupid.
-I hate the new player comparisons when doing substitutions. The six-sided morphed hexagon approach I think was supposed to give players an at-a-glance comparison, but I don't like it it all.
The sum of all this is that the frustration level has dropped by about 90%. My friend, who was very skeptical about this year's release after FIFA14, played and lost 0 to 2 against Man City, but we didn't feel like we were ineffective. It was a great game and we truly deserved the loss. I can't express to you all of the little things that contribute to how much of an improvement this game is over FIFA14, but I've tried.
Hope this helps some people make decisions about buying the game.