Starcraft 2, Brutal difficulty walkthrough with commentary
Mission 21: Engine of Destruction
One of the hardest missions in the game. Escort the Odin as it destroys 5 enemy bases. For this guide, I used mass wraiths, which do good enough damage versus air and poor damage versus ground. Since the enemy has very little in terms of detection, cloaked fighters such as wraiths, banshees, and ghosts are effective. Make sure to snipe the battlecruisers and siege tanks about all else, as they do the most damage to the Odin. Repair during battles with science vessels and SCVs, though the SCVs will get slaughtered and must be continuously replaced. During the battle at the 2nd base, get a command center ready to take over the mineral patch. You will need the extra resources badly, not to mention the extra SCV production capability.
Starcraft 2 Mission 21: Engine of Destruction walkthrough on Brutal (w/commentary) Part 1 of 2
Starcraft 2 Mission 21: Engine of Destruction walkthrough on Brutal (w/commentary) Part 2 of 2