Choose both.

Play each option once.

U need to destroy the three core first before the mothership shield going down...

Just like the movie indepence day.......

Kakakakaka

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Added on August 2, 2010, 5:46 pmI like the campaign where Fight Zerg till the last standing protoss....

Hahahaha... that campaign is the most fun .........

Yes, I also think Haven's Fall is quite easier than saving it, the mothership is quite powerful on its own and it spawns other units when you attack it.
Even if you can't clear up the whole cluster of Zerg you can do a suicide rush to kill the Infection-spreading building which has low health when it's not completed yet.