Unlocking this mode might require the completion of each different custom mission. Also, rank played may be a determining factor. This involves mission 1 through 8 with all three modes (Demolition, Neutralize, and Disable). You can complete the resulting mission offline or shared with friends that yield 5000CE per play through. It is located in "Custom Missions" as Mission 9 (M9). Remember that the enemies here are tough, and only veterans should tryt to charge "Rambo" style. Also, after completion "Maid" becomes an enemy type for custom missions and you get "Ms. Blue" (and other colors) with "Mr. Red" (the sniping butler/server) available as special characters in Competitive mode while playing as a Merc. There are ten cupcakes you must retrieve to complete the mission:
CUPAKE - LOCATION Cupcake 1 - You will walk past it. Down the stairs in the building, turn hard right. There is a shelf against the wall. Cupcake 2 - The first corridor after the first cupcake. Go left at the split. The cupcake is sitting on a control panel. Cupcake 3 - Through the doorway. Take it off the table. Cupcake 4 - Before going outside through the reinforced door, go upstairs. It is on the left of the table in the room. Cupcake 5 - When outside, look at the far right corner. There is a tree in a square concrete planter. It is on the approaching side. Cupcake 6 - After taking the stairs and tunnel, you will reach a grassy area. Go to where the snipers are on the high path. It is on a rock in a small clearing in the middle. Cupcake 7 - The fountain in the picture is on the right side as you approach, and the cupcake is on the back side. Cupcake 8 - It may be difficult to find at first. Go to the dumpster directly ahead from the stairs. With the cars on your right you will see a broken crate looking object. It is on that object. Cupcake 9 - The piano on the bottom floor of the mansion building. Cupcake 10 - The top floor taking the stairs that lead right to a door. It is on a desk all the way in the back of the room on the left wall.