Try this on Medium. with zone 6 there are two extra nuke pick ups. Each person should grab one making them each have 6 before reaching zone 29. When you see a group of ships come up behind you wait a sec and have either you are your partner nuke. Have him or you use your nukes first then when empty it's the other persons job. When you see mines just use your rockets. I let some pass and still got the achievement. Now there will be a huge ship in an open hangar that has turrets on it. I'm sure this one counts use a nuke near it to bring it down. Just use nukes when ships come up from behind. You should have enough nukes and rockets to get the job done.