Starcraft 2, Brutal difficulty walkthrough with commentary
Mission 10: The Dig
In this awesome level, you have to defend a laser drill from constant Protoss attacks while it slowly burns through a temple door. Use your newly-aquired siege tanks to their fullest by basically filling your base with them. It's also very important to expand to the lower right immediately; the extra income will be necessary the kind of tank production you need to beat this. Also, there are a couple of research points to be won by securing relics. The relics aren't hidden or even well defended, but the mission is so intense and fast moving that you will have a difficult time pulling yourself away from defense to put a marine force together. Don't be afraid to skip the research if you find the mission to be too hard. Also, don't listen to the game's advice about using the drill to kill archons; use it to kill colossi and immortals instead.
Starcraft 2 Mission 10: The Dig walkthrough on Brutal (w/commentary) Part 1 of 2
Starcraft 2 Mission 10: The Dig walkthrough on Brutal (w/commentary) Part 2 of 2