Cleansing (achievement)

Cleansing is an Halo 3 Achievement.

It is earned when someone finishes the Campaign mission Floodgate on the Normal, Heroic, or Legendary difficulties, and gives 30 Gamerpoints to the player.

It is represented by a blue plate with a roman numeral V (five) on it.

The level must be played from mission start in order to unlock the achievement.