Skunked Achievement in Halo: The Master Chief Collection

This achievement must be earned online in a matchmade game.

In this 6v6 game type, the objective is simple: one team defends and one team attacks; the attacking team needs to "contest" one of two generators in Phase 1 and if they are successful, go onto a similar objective in Phase 2. If the attacking team successfully contests one of the two generators in the second Phase, then they will finally be able to capture the core in a centralized, yet heavily-guarded area on the defense team's turf and extract said core to safety. If the core is extracted, the attack team wins; if, during any phase, the defense team prevents the attacking team from advancing for the allotted time, they will win.

For the purposes of this achievement, you must, while on the defending team, prevent the opposing team from capturing either generator for the allotted time (4 minutes). If you are on the attacking team at the start of a match, don't worry, the teams will switch sides after the first round.