Well while I never quite understood how he survived the first game. Sergeant Johnson died near the end in the 3rd game, killed by guilty sparks because he activated the halo within the ark too early. Last thing he does before dying is handing cortana back to chief and telling him to send Johnson out with a bang, almost made me cry the first time I saw it.

Correct, although I did kill him in the first game.

I acually were a bit surprised when I saw him in the second game after witnessing the legendary ending of the first. Hehehe me and my friends spent hours trying to kill him in the 3rd game, just to see if it was possible.. May I have a legendary quesstion now? :D