Assassin's Creed

# Completion bonus

Successfully complete the game. When the Memory Blocks are played again in Story mode, you can kill anyone without penalty. Additionally, you will be able to use Eagle Vision at any time regardless of Synchronization levels inside of the Animus.
# Escaping from guards

Go to a high roof when chased. Kill the guards that appear. After a few kills, they will either run or give up.
# Easy kills

Note: Only attempt this technique if they are fluent in the Rank 2 skill "Counter" and they have enough Synchronization bars; one and a half rows of bars will do. When in battle, equip your hidden blade. With this equipped, all of your counters will score an instant kill. You can even instantly kill tougher ranked guards (for example, the Teutonic guards in Acre when hunting Sebrand). Also, most of the time using the hidden blade in battle will scare the last one or two (even three if you are lucky) guards, causing them to run away. However, because you do not have a weapon that is sufficient enough to block a full sized enemy blade, all incoming attacks will hurt you.

While in battle, if you see a guard you are fighting physically emote in any way (for example, taunting you or cowering in fear), press Low Profile Assassinate while facing them to score an instant kill without having to counter.

The best weapon for more than four guards or thugs is the Short Blade.
# Easier interrogations

After you get the "target" to a safe area to "interrogate" them, punch them first then "grab" them for faster completions. It will take about two grabs to quickly finish them. However, in the last three quarters of the game, you may have to grab them up to four times.
# Easier game

To lower the time needed to complete the game and decrease the difficulty of each major assassination, do the following in order (with the exception of Masyaf):

Visit the Assassin's Guild.

Scan the city by first climbing all of the view points.

Rescue all the citizens from the thugs. You will need the help after a major assassination.

Successfully complete all of the informant's missions (to get all the valuable information you can).

Pickpocket the shysters in all of the pickpocket missions (for information to the Guild).

Once all of these are completed, go back to the Assassin's Guild to start the major assassination mission.

# Unlocking your bedroom door

When you go to bed after Memory Block 2, you will notice your closet door is open. Press any button to get a piece of paper Desmond notes as a code. The code will unlock your bedroom door, which will allow you to be able to go out as often as you like after you go to bed, as well as to open the meeting room area. You can also pick up various items to unlock Lucy's password.
# Decoding e-mails from Lucy's computer

One item you can pick up after being able to unlock your bedroom door is Lucy's password. You can then investigate her e-mails, which entail a short secondary story line. After you complete the last Memory Block, go back outside your room. Go to Lucy's computer. In "Deleted Items" is an e-mail which entails her talking to someone about a rescue, then the last reply comes back as:

WondEr Why It is everyone Laughs at you?
i'll Let you guess.
let's just say she's proBably gEtTing it bigger and better from someone else tHat isn't you.
how can you hope to compEte?
REst asSured there are sOme gOod ways.
click the liNk to see!

Removing the capital letters out of the message decodes the message as:

WE WILL BE THERE SOON

# Hidden messages

After killing Al Muaiam and returning to the real world, listen to the conversation about how they going to kill you. Turn on your Eagle Vision, and look at the floor. There are some mixed up letters on both sides of the Amnius. You should see on the side closest to the main door:

M O R Y M N O E S
E N C E O L C H T
H O N B T L O T C
T D E O S A T O A
P E D S N L S T F
L D D U O O E T E
E A I E I R I N T
H S H K T T K E R
T U A A A N S S A

To decode this, start reading at the bottom right hand corner to the top right hand corner, so you will start at "A" and stop at "S". It will spell a real word. Do this for all of the columns and it will read:

ARTEFACTS SENT TO THE SKIES TO CONTROL ALL NATIONS TO MAKE US OBEY A HIDDEN CRUSADE DO NOT HELP THEM

Next, do the same thing to the mixed letters on the other side of the Amnius:

A
D R H
O O D T M
W H B I T D O
E U S Y S I N S E
A R O O M R E A Y N R
I S E Y T N I D L M I D E
T W I H W Y I E A U D A Y H T

It will spell out:

THEY DRAINED MY SOUL AND MADE IT THEIRS I DRAINED MY BODY TO SHOW YOU WHERE I SAW IT
# Defeating the Master

When fighting the Master, he will take away your ability to use radar and make it difficult to see. This also allows him to hit you once and kill you. Lock on to him, and use a throwing knife against him. This will take away his power to blind you and make him easier to kill.

The first part is simple. Take out your sword, as you will be fighting all your previous assassination targets. They are fairly easy to kill. Only one counter is required to kill each of them. For the second part, as soon as Al Mualim releases you, use your Eagle Vision. The real Al Mualim is the one in yellow. Focus your attacks on him. In the third part, Al Mualim takes away your synchronization bar and radar, allowing him to kill you in one hit. Take out your throwing knives. Look for the Piece of Eden in his hand. Once you see him, throw a knife at him. Then, just counterattack/grab break him. Keep repeating this until he says, "Damn you Altair!" Finish him off with your hidden blade or keep attacking him with your sword until he is dead.
# Defeating William of Montferrat in Acre

After the guards (or most of them) leave William, drop down from the castle, and slay William. Then, "de-target" or deselect, and run up into the castle buildings and battlement to get away. This is the fastest way of completing the mission.
# Transformers reference

Go to the southwestern-most vigilantes in the poor district of Damascus. On one of the buildings around them, you should see an outcropping in the wall, climb on it to see it looks exactly like G1 Optimus Prime in vehicle mode. Note: There may be more than one outcropping in the area, so look carefully. If you lose sight of the vigilantes, you have gone too far.