Wetwork (achievement)

From Halopedia, the Halo wiki

Wetwork is an achievement in Halo: The Master Chief Collection. It is unlocked by activating the enemy base's waterfall and, before it stops, grabbing the flag in Capture the Flag on Shrine in Halo 2: Anniversary multiplayer. The achievement is worth 5 Gamerscore and can be unlocked in both matchmaking and custom games.