**Halo 3 in MCC: Floodgate achievements without mixing up the old scoring rules**

**Halo 3 in MCC: Floodgate achievements without mixing up the old scoring rules** *Mission spoilers.* Floodgate is short, but its achievement instructions get confusing when an old Halo 3 walkthrough is treated as an MCC guide. The original scoring target and time-bonus table aren't automatically the collection's numbers. For **MCC**, the useful checklist is: - **Cleansing:** complete Floodgate; Easy counts. - **Dambuster:** finish below **15:00**. - **Exterminator:** beat **25,000 points**. - **Skulltaker Halo 3: Fog:** collect the opening skull on Normal or higher, starting from the beginning. - **Milk Carton:** find the missing-person poster in the opening storage passage. There is no collectible terminal on Floodgate. The device with Cortana's message at the end finishes the story mission; it isn't an extra terminal achievement. **Get the two opening stops out of the way** Start on Normal, keep the battle rifle and watch the right-hand roof as you enter the city. Shoot the skull-carrying Flood during its crossing and collect Fog from where it falls. Then inspect the poster on the floor in the first recessed opening on the right after the turn into the narrow passage. If you miss the carrier, use an earlier checkpoint only if it really precedes that jump. Otherwise restart. There is no reason to complete the whole mission before trying again. For the poster, try solo if split-screen refuses to register the inspection; that problem appears in community reports. Once those unlocks are confirmed, your later runs don't need either detour. **Dambuster: a clean route is enough** Use Easy with the timer visible for a basic par-time attempt. There is no requirement to do this on Legendary or with the Fog skull enabled. Move down into the warehouse, continue through the outdoor fighting and enter the crashed ship. Fight what blocks you, but don't spend several minutes hunting isolated Flood behind crates after the route is open. Have a close-range weapon available for attackers that actually reach you and keep a ranged answer for enemies firing from an elevated position. The interior of the ship is the last navigation section. Follow it to the blue-lit story device and interact. Don't start shooting every organic blister on the way; creating another small swarm buys you nothing. Advanced runners use launches and other movement tricks here. You don't need those just to beat fifteen minutes. Learn the ordinary doors and outdoor route first. A shortcut that fails twice is not a shortcut for that attempt. **Exterminator: now the enemies matter** Use scoring mode and watch the total. This time, skipping most of the opposition can leave you at the ending with a quick completion and not enough points. Choose a difficulty you can handle efficiently, then add scoring skulls selectively. Catch is commonly recommended for this Flood-only mission because the Flood do not throw grenades. That doesn't make every other skull harmless. Fog removes useful information, Famine makes scavenging less generous, and death-related modifiers can turn a manageable run into repeated restarts. Don't take a guide's suggested setup as a guaranteed score. Your actual kills, deaths, pace and modifiers are what matter. Fight the warehouse groups from cover, prioritize dangerous ranged enemies outside, and collect points while keeping the route moving forward. Repeated deaths and friendly fire are expensive ways to lose progress. The MCC target is **25,000**, not the original game's 15,000. Aim above the target with enough time left to finish safely; complete the level and check the final scoring result rather than quitting as soon as a live number looks good. **A sensible order** Do the opening collectibles, learn the normal route, take the quick Easy completion, then practice scoring. If a timed or scored attempt fails, compare the actual result with the target before blaming the unlock system. A score below the threshold or a finish over fifteen minutes is a different problem from a verified qualifying result that hasn't registered yet.