Third times the charm right? Complete the game on Hard difficulty. Finally challenging - in parts. Overall, the game is not very hard, there are however a few points throughout the game that really get tough. To help out a little I have posted tips in each of the episode completions achievements.
Overall you need to be far more careful when playing on Hard. Use your cover and crouch (click the
Button to crouch), refill your health (hold the
Button when you have animus stored), and always reload your weapon (click the
Button to reload your weapon) every chance you get.