Don't Touch That!
From Halopedia, the Halo wiki
Don't Touch That!
Don't Touch That! is an achievement for Halo: Reach multiplayer matchmaking added to the Defiant Map Pack with the release of Halo: Combat Evolved Anniversary. The achievement is earned by preventing the attacking team from touching the flag in a matchmaking 1 Flag CTF game. This applies not just to one round, but to the entire game. Thus as most 1 Flag CTF games are two rounds, players must prevent the opposing team from touching their flag in either of them.