when you have Notorius status, where all guards will be more quick to attack.

Learn the basics of combat in Assassin's Creed II, including enemy attack patterns and how Ezio's health is represented.

Enemies will surround Ezio and typically attack one at a time, but there are instances where more than one will attack simultaneously. While in combat, Ezio can only lock onto one enemy at a time, but he can switch targets by using the Left Analog Stick to point toward a different enemy when attacking.

Your health is represented by the white squares in the top left of the HUD (Heads-Up Display). When you take damage, the severity is measured by these squares. If you lose a whole square, it will not be replenished except by medicine or a doctor. If you lose only a part of a square, it will replenish itself if you don't take any further damage for a few seconds. Enemy health is represented by the red squares above their heads.