StarCraft II achievements.
SC2 Easy Achievements: Easy way to get the Feat of Strength: Monster Mash. 1.Kill everything up to the room where the Brutalisk is with your marines/medics/Raynor. 2.Activate the A.R.E.S. with anti-armor missiles and just send it to kill the brutalisk.
How to unlock the Secret Mission: Piercing the Shroud. 1 . Destroy the building at the South East of the map. Get the item that drops. 2 . Finish the mission. **Be sure to do that before going to Char, or load a saved game from before going there.**