Assassin's Creed II
50 Achievements
1,000
No-hitter
Kill 10 enemies while remaining in conflict without being hit.
20
How to unlock the No-hitter achievement in Assassin's Creed II - Definitive Guide
To unlock this achievement you must first provoke a group of guards into chasing you. This is easiest in the San Marco district of Venice as there are a lot of guards there right around the restricted area. Before you do, if you have them (I suggest not attempting this achievement until you do have them), arm your smoke bombs by holding to open the weapon wheel and moving the to the bottom left to select them. Keep running until more guards enter the chase. When you have 10 or more following you, as they gather around you, quickly throw the smoke bomb down with then select your hidden blades () and begin assassinating them. Once the smoke bomb starts to wears off, select the smoke bombs again and throw another one, and repeat the process. Keep going until you eventually kill 10 guards for the achievement.
You obtain the smoke bomb pouch during the memory ‘The Cowl Does Not Make the Monk’ in DNA Sequence 5. You can acquire smoke bombs, up to three, from a Blacksmith for 350ƒ each after that.
Thanks to XCVii007r1 for the video:
This one sounds harder than it actually is. Once you can counter that's all you really need for this trophy. Get into a big group of guards and make sure there is enough there. If there isn't enough guards simply provoke the guards in some way and run into another big group of guards and there should be enough. You must kill 10 enemies without leaving battle without being hit. Just continue to counter until you've killed 10 enemies. This may take a few tries but once you master the counter skill this should be no problem at all.
Alternatively you could do what is shown in this video. For this method to work though you must have smoke bombs available to you. Thanks XCVii007r1 for the video.