The Eagle and The Apple - 1191: This is pretty straight forward. Complete Assassin's Creed's story mode and sit through the credits. Bam. Achievement.
Eagle's Will: This requires you to kill 100 enemies without dying. No, not in the same fight, but just killed 100 enemies between deaths. Simply pick a lot of fights, use a LOT of counters (RT + X) and a lot of guard breaks (A followed by X) and if things look grim, don't be afraid to run.
Eagle's Flight: This one is tricky, survived 10 minutes in open combat. Though, it's not impossible. I found a really easy way to do it. Simple go to Damascras and go to the poor or middle district (I THINK it's the poor, but if it's not, go to the middle) Here, the lesser guards cannot guard break or throw. Find a couple of them, lock onto one, put your back to a doorway, put the controller in between your legs so that you're holding RT with your legs, and read a book for ten minutes. If a high guard comes by, he can throw, so take care of him before retreating back to your door.
Eagle's Prey: This is actually pretty easy, and requires the assassination of 100 guards. I find this easy anywhere. Either go to the rooftops, where it's very easy to get behind guards and find them alone, and if they notice you, pounce on them and do a noisy assassination, which won't be notice unless there are other guards on the roof. Also, in a saving the citizen game, when you walk up, the guards are unaware, so you can stealth kill one, or if it takes them a moment to realize, two! Lastly, you can simply walk around the city stealth killing guards. Be careful with this method though, if you kill them close to another guard, you will get noticed, and if you come back to the scene of the crime, and you haven't blended, you may get noticed.
Eagle's Challenge: This involves defeating 25 guards in a SINGLE fight. This sounds really hard, but you should get it on Memory Block 7 while going through the battle field. If not, then simply go a city, and run around attracting guards until you have 25 on your tail, and take them all out.
Eagle's Swiftness: This one is extremely easy. Just get 100 counter kills (RT + X when an enemy starts to come at you) within different fights. This should be your primary move you're using in fights, so you should get it before then end of the fourth or fifth memory block. If you don't want to do it this way, you can do it in the training ring back at your base, since those fights count towards this count.
Eagle's Dive: Also pretty easy. Just get 50 combo kills within different fights. To do a combo kill, swing your sword at your enemy, and right when it makes contact with his sword, hit X again. In you don't want to do it this way, then just do it in the training ring.
Eagle's Talon: This should go hand-in-hand with the Eagle's Prey achievement, because this one makes you preform 50 stealth assassinations. This one is more flexible however, and can be done without killing guards. If you want, when the crazy dude who just LOVE to shove you come around, or those idiot beggars, simply shove your hidden blade in their stomach. This also works on normal citizens. Without their knowing, the population of the city has dropped by 50...
Eagle's Dance: I got this one without realizing I was trying to get it, as it is VERY easy. Simply do 50 leaps of faith. You should remember these from the tutorial level (IE, the first one) Simply look for a place where a line of birds is perched, and sprint (RT + A) where they were sitting. You should dive off into a bale of hay. You can do jumps over and over if you like to get this one, or you can get it while doing all the view points or escaping the guards. Either way is fine.
Eagle's Eye: Kill 75 guards with throwing knives. The ones on the roofs are the easiest targets, so toss knives at them. Be careful though, done this way can cause them to fall from the roof, scaring people in the street, and attracting attention. (As well as creating a spot where guards are extra suspicious...) Another good way is to attract the attention of a lot of guards, climb a ladder to a roof, run a little ways away, and wait for each guard to file up the ladder, killing them all with knives. If you run out, go down to the streets and look for people wearing brown cloths with large pouches on their bums. Lock onto them, and pickpocket them by walking close to them and holding B. This will let you pickpocket 5 throwing knives from them. This also contributes to the Hands of a Thief achievement.
Hope I helped, now go be the best damn eagle ever!
Added by: imaloony8.0 Oct 12th 2008, ID#3274