I have this thing where when I buy a game I always start out on the hardest difficulty. And let me tell you something; legendary is a pain in this game. Unlike Halo 3 or Reach, there is no way to walk past the enemies without dying. This is a “sit-and-wait” type game.
But they got everything right in this game. The Assualt rifle holds 60 rounds, the pistol can snipe, and the plasma grenades take 5 seconds to explode, and when they do, everybody dies. All of the sound effects are identical to the original and the physics are exactly the same. The graphics are upgraded substantially, but it still isn't as good as Reach's.
All in all, everything, except the graphics, is identical to the original Combat Evolved. It’s a ton of fun and you will nearly die from a nostalgic overdose.
Now I want to see an updated version of Halo 2.