Another Assassin's Creed game this year. Ubisoft sure are filled with surprises by releasing an Assassin's Creed game every year. The downside to this move is that the quality of the new game may not differ or worse than the previous game. Fortunately, Assassin's Creed: Revelations improves from the previous game in quite a number of areas, with some exceptions to the main storyline and some parts of the gameplay itself.
Story
The game takes place directly after Assassin's Creed: Brotherhood, where Desmond fell into coma after being forced to kill Lucy in the Vault at Rome. While in the Animus, he met Subject 16, who's mind somehow survives in the Animus, and told him in order to wake up from the coma, Desmond needs to relieve both of his ancestor's memories until there is nothing more important to be shown, both Ezio's and Altair's memories.
As for Ezio's storyline, he went to Masyaf to find clues about the Assassin order and other secrets. Little did he know that Masyaf is crawling with Templars, who fought Ezio, and caught him and was about to kill him. Ezio managed to escape, and he needs to find the keys to enter Atair's library, a secret room in Masyaf.
Here's the thing about the storyline. I love Ezio's and Altair's storyline in the game, but the main storyline in the present day is very disappointing. Not much development about it, and once you finished the game, you will feel that the game ends too soon. You will be saying or asking things such as: "Wait, that's it?", "What the hell just happened?", "The ending sucks!", or etc. To avoid spoilers, some of the revelations in the game can be shocking, but not enough of it.
Characters interaction and development in the game is quite good, but only for the Ezio's and Altair's era. In the present day, don't expect to talk to much people since Desmond is stuck in a coma. My favourite new characters in the game would be Yusuf, another Master Assassin, Prince Suleiman, prince of Istanbul, and Sofia, a rather charming young girl who would be love interest of Ezio after knowing each other for quite some time. I do feel sympathetic about Altair a lot more in this game compared to the first game, and I always endear Ezio since he is one of my favourite characters in games.
Gameplay
The gameplay pretty much the same as the previous Assassin's Creed games. You have access to your signature hidden blades to assassinate people in stealth or public, a sword, a short weapon, hidden gun, crossbow, etc. There are several new stuffs that Ezio can use in his adventures to fight his enemies. You also can still hide in the crowd to avoid pursuers, sit on a bench to hide, or etc. Same old hide and fight techniques.
Firstly, you have now access to hookblade, which will acts as both navigation tool and killing tool. The hookblade replaces and acts as your second hidden blade, and it allows you to show off several new moves in the game, such as hook and run, an evasive maneuver, or hook and throw, an offensive maneuver that allows you to kill an enemy, and etc. It also acts as climbing tool that allows you to climb buildings, walls much faster, and allows you use ziplines to travel quickly from one place to another.
Secondly, you can now choose and customise bombs to fight your enemies. There are three categories of bombs, one is for killing, one is for tactical, and one is for diversion. Creating bombs is a new to this series, since you can mix and match the ingredients used to make a different type pf bomb. For example, by mixing a Datura powder, any type of gunpowder, and any types of bomb casing will result a bomb that allows you to poison your enemies. You can even customise your bombs to be a tripwire bomb or even a timed bomb. Experiment each ingredients to create bombs that is effective for certain missions. For example, missions that require you to be stealth will often leads you to create more diversion bombs such as Cherry Bombs to distract enemies. Although it is not necessary to use bombs to complete missions, but they are essential in getting 100% Synchronisation for each Memory in the game. However, you are mandatory to use bombs in certain missions since you can't progress in the game without using it. Other than that, it is optional.
You now have access to Eagle Sense, an improved version of Eagle Vision from the previous games. This time, you can track enemies' patrol routes while you use that ability, which allows you to set a trap or anticipate their coming and kill them one by one. Eagle Vision also allows you see through smokes, so use it when you are using Smoke Bombs to mask your killings in the game.
The combat in the game feels the same as the previous game's combat, but I felt that the enemies are slightly more aggressive than the previous Assassin's Creed games, which is a good thing. The killing streak also returns, which allows you to kill enemies instantly if you are not interrupted while doing it.
Den Defense is a minigame that allows you to protect your Dens from being taken by the Templars again. You need to place your Assassins in certain places to overcome several waves of Templars. After winning several Den Defenses, it will become much harder, and there will be more powerful Templar units that can devastate you, such as Stalkers, that will kill the Assassins on the rooftops. You can also shoot your hidden gun to kill any Templars left, kill Stalkers, and use it to concentrate the attack force on a specific target, like a cannon barricade. You can use your cannon to kill multiple enemies at the same time. This is a unique addition to the game, but it can be overpowering since the minigame will become much more harder, and the Templars will always retake the Den you control, forcing you to kill the Den Captain(s) again and again. It is highly recommended to quickly train your Assassins to Master Assassin level to avoid your Den being overtaken by the Templars.
In order to Renovate shops such as Bank, Blacksmith, or etc, you need to take over a Den from a particular district by killing the Den Captains. Also, by renovating shops, you can gain a certain amount of income per 20 minutes. The more shops you renovated, the more income you can get. This is important because money is not easy to get in the game, other than completing Memories for every Sequences. You can use the money to buy new weapons, armours, equipment, medicines, etc. Buying good armour is highly recommended to have a better chance in fighting tougher enemies like Janissaries in later Sequences.
Please be noted that having your Notoriety level at the maximum will cause Templars to attack one of the Dens. Bribe Heralds or kill a certain Templar target to lower your Notoriety.
Sending multiple Assassins to a high level missions is a great way for them get experience, but be noted that they will share experience equally. For example, if the mission is worth 1500 experience points, sending an Assassin alone to the mission will net him/her full experience points, whereas sending three Assassins to the mission will net them 500 experience points each. Missions will be completed via the required time shown in each mission details. Low level missions will take less than 10 minutes (real time) to complete, whereas high level missions will take more than 15 minutes to complete.
Once they have reached certain level, they will initiate a certain side mission which requires you to kill a target. However, these side missions have two parts, which will be initiated when they reach level 10 or 11, and another in level 14. Another requirement for them to become Master Assassin is to place them as the Den Captain for any Den. Once they become Master Assassin, that particular Den will not be attacked or taken over by Templars. Take note that having Master Assassins are quite formidable in fighting large group of enemies when called.
The gameplay is more or less refined with unnecessary new features such as Den Defense and Desmond's first person view platforming missions. The core gameplay mechanics is good as always, with some new aggressive enemies unlike previous Assassin's Creed games. Unfortunately, it did not offer much new gameplay mechanics, except the addition of the useful Hookblade, bombs customisation as well as Den Defense and Desmond's FPV missions. The latter two can be rather boring to play and indulge, but the hookblade is a great new tool as well as the freedom of customising your bombs is rather great. However, players who played previous Assassin's Creed games should not expect that this game is anymore different or better than the previous games.
Story

Desmond is now in coma, and is placed in the Animus to save his mind from being deleted.
The game takes place directly after Assassin's Creed: Brotherhood, where Desmond fell into coma after being forced to kill Lucy in the Vault at Rome. While in the Animus, he met Subject 16, who's mind somehow survives in the Animus, and told him in order to wake up from the coma, Desmond needs to relieve both of his ancestor's memories until there is nothing more important to be shown, both Ezio's and Altair's memories.
As for Ezio's storyline, he went to Masyaf to find clues about the Assassin order and other secrets. Little did he know that Masyaf is crawling with Templars, who fought Ezio, and caught him and was about to kill him. Ezio managed to escape, and he needs to find the keys to enter Atair's library, a secret room in Masyaf.
Here's the thing about the storyline. I love Ezio's and Altair's storyline in the game, but the main storyline in the present day is very disappointing. Not much development about it, and once you finished the game, you will feel that the game ends too soon. You will be saying or asking things such as: "Wait, that's it?", "What the hell just happened?", "The ending sucks!", or etc. To avoid spoilers, some of the revelations in the game can be shocking, but not enough of it.
Characters interaction and development in the game is quite good, but only for the Ezio's and Altair's era. In the present day, don't expect to talk to much people since Desmond is stuck in a coma. My favourite new characters in the game would be Yusuf, another Master Assassin, Prince Suleiman, prince of Istanbul, and Sofia, a rather charming young girl who would be love interest of Ezio after knowing each other for quite some time. I do feel sympathetic about Altair a lot more in this game compared to the first game, and I always endear Ezio since he is one of my favourite characters in games.
Gameplay

Expect a lot of climbing buildings, killing a lot enemies, etc.
The gameplay pretty much the same as the previous Assassin's Creed games. You have access to your signature hidden blades to assassinate people in stealth or public, a sword, a short weapon, hidden gun, crossbow, etc. There are several new stuffs that Ezio can use in his adventures to fight his enemies. You also can still hide in the crowd to avoid pursuers, sit on a bench to hide, or etc. Same old hide and fight techniques.

Hookblade is useful to travel from one place to another quickly.
Firstly, you have now access to hookblade, which will acts as both navigation tool and killing tool. The hookblade replaces and acts as your second hidden blade, and it allows you to show off several new moves in the game, such as hook and run, an evasive maneuver, or hook and throw, an offensive maneuver that allows you to kill an enemy, and etc. It also acts as climbing tool that allows you to climb buildings, walls much faster, and allows you use ziplines to travel quickly from one place to another.

You can customise your bombs to suit the current mission's nature.
Secondly, you can now choose and customise bombs to fight your enemies. There are three categories of bombs, one is for killing, one is for tactical, and one is for diversion. Creating bombs is a new to this series, since you can mix and match the ingredients used to make a different type pf bomb. For example, by mixing a Datura powder, any type of gunpowder, and any types of bomb casing will result a bomb that allows you to poison your enemies. You can even customise your bombs to be a tripwire bomb or even a timed bomb. Experiment each ingredients to create bombs that is effective for certain missions. For example, missions that require you to be stealth will often leads you to create more diversion bombs such as Cherry Bombs to distract enemies. Although it is not necessary to use bombs to complete missions, but they are essential in getting 100% Synchronisation for each Memory in the game. However, you are mandatory to use bombs in certain missions since you can't progress in the game without using it. Other than that, it is optional.

Ezio now have Eagle Sense, an improved version of Eagle Vision.
You now have access to Eagle Sense, an improved version of Eagle Vision from the previous games. This time, you can track enemies' patrol routes while you use that ability, which allows you to set a trap or anticipate their coming and kill them one by one. Eagle Vision also allows you see through smokes, so use it when you are using Smoke Bombs to mask your killings in the game.
The combat in the game feels the same as the previous game's combat, but I felt that the enemies are slightly more aggressive than the previous Assassin's Creed games, which is a good thing. The killing streak also returns, which allows you to kill enemies instantly if you are not interrupted while doing it.

Den Defense is a unique minigame, but can be too hard for some players and felt unnecessary.
Den Defense is a minigame that allows you to protect your Dens from being taken by the Templars again. You need to place your Assassins in certain places to overcome several waves of Templars. After winning several Den Defenses, it will become much harder, and there will be more powerful Templar units that can devastate you, such as Stalkers, that will kill the Assassins on the rooftops. You can also shoot your hidden gun to kill any Templars left, kill Stalkers, and use it to concentrate the attack force on a specific target, like a cannon barricade. You can use your cannon to kill multiple enemies at the same time. This is a unique addition to the game, but it can be overpowering since the minigame will become much more harder, and the Templars will always retake the Den you control, forcing you to kill the Den Captain(s) again and again. It is highly recommended to quickly train your Assassins to Master Assassin level to avoid your Den being overtaken by the Templars.
In order to Renovate shops such as Bank, Blacksmith, or etc, you need to take over a Den from a particular district by killing the Den Captains. Also, by renovating shops, you can gain a certain amount of income per 20 minutes. The more shops you renovated, the more income you can get. This is important because money is not easy to get in the game, other than completing Memories for every Sequences. You can use the money to buy new weapons, armours, equipment, medicines, etc. Buying good armour is highly recommended to have a better chance in fighting tougher enemies like Janissaries in later Sequences.
Please be noted that having your Notoriety level at the maximum will cause Templars to attack one of the Dens. Bribe Heralds or kill a certain Templar target to lower your Notoriety.

You can recruit Assassins like Assassin's Creed: Brotherhood. Only this time, training them to Master Assassins have their own side missions.
As in Assassin's Creed: Brotherhood, you can recruit Assassins by helping innocent civilians from danger or complete their challenges. You can recruit up to more than 10 Assassins, and you can recruit more as you takeover more dens. You can call them to help you to kill unsuspected enemies on the roof, or help you in a fight between you and multiple enemies. You can only train up to 7 Master Assassins. Each Assassin have their own levels, and will gain Experience needed to rank up a new level by fighting an enemy in a battle, kill an enemy stealthily, or by sending them on missions in Mediterranean Defense. Sending them to Mediterranean Defense missions is the fastest way to gain quick levels. The success of a mission will depends on the Assassin's level. The higher the level, the better the success rate.Sending multiple Assassins to a high level missions is a great way for them get experience, but be noted that they will share experience equally. For example, if the mission is worth 1500 experience points, sending an Assassin alone to the mission will net him/her full experience points, whereas sending three Assassins to the mission will net them 500 experience points each. Missions will be completed via the required time shown in each mission details. Low level missions will take less than 10 minutes (real time) to complete, whereas high level missions will take more than 15 minutes to complete.
Once they have reached certain level, they will initiate a certain side mission which requires you to kill a target. However, these side missions have two parts, which will be initiated when they reach level 10 or 11, and another in level 14. Another requirement for them to become Master Assassin is to place them as the Den Captain for any Den. Once they become Master Assassin, that particular Den will not be attacked or taken over by Templars. Take note that having Master Assassins are quite formidable in fighting large group of enemies when called.

Control Altair in his young and old days at certain points in the game.
At certain points in the game, you need to control Altair to complete certain Memories in the game. Unlike Ezio, he has access to a rather limited equipment. However, he has the maximum health from the start, so it is understandable. He now has access to Kill Streaks as well, unlike in the first game, as well as can use his Hidden Blade as a fighting weapon.

Playing Desmond's own FPV missions can be rather boring, except his own narration about his past life.
In this game, you can play some first person view platforming missions using Desmond. However, it can be rather boring since it did not offer much playing value except getting from point A to point B. However, when you reach certain points in the stage, you can hear Desmond's narration about his past life. His narration on his past life is rather interesting, but does not offer any new information about himself or others. In order to play all of his FPV (first person view) missions, you need to collect a certain amount of Animus Data Fragment in the game to unlock a new FPV mission.The gameplay is more or less refined with unnecessary new features such as Den Defense and Desmond's first person view platforming missions. The core gameplay mechanics is good as always, with some new aggressive enemies unlike previous Assassin's Creed games. Unfortunately, it did not offer much new gameplay mechanics, except the addition of the useful Hookblade, bombs customisation as well as Den Defense and Desmond's FPV missions. The latter two can be rather boring to play and indulge, but the hookblade is a great new tool as well as the freedom of customising your bombs is rather great. However, players who played previous Assassin's Creed games should not expect that this game is anymore different or better than the previous games.