Mama

Mama is the first boss of The Facilities, appearing in E2M5: The Escher Labs. She is the first and original Cowgirl, possessing the same attack pattern and animations but significantly scaled up. She rests in a hollow grain silo which also contains the blue key.

Strategy
For Mama, the player should be equipped with the Riveter. One rivet damages for 500 HP (300 direct+200 splash), and she falls fairly quickly (12 direct hits). However, she can usually kill the player if she scores two direct hits with her "rockets". Her mechanics make fighting her in an open area suicidal. Strafing or finding cover is a problem due to the flat arena landscape. The best terrain option for Mama is leading her around the silo where she was held. It can serve as good cover and allows to easily break line of sight. When she moves to a firing stance, you are free to shoot 1-2 rivets and continue playing the deadly game of ring-around-the-rosie. Be sure to watch out for splash damage from both you and her.

Alternatively, she goes down even quicker with a charged sword if you have it from the secret at the spiral hallway earlier in the level (it is on the right, with a mismatched texture). 7 hits are necessary and the long reach of the charged sword in combination with the aforementioned circling around the silo makes this strategy surprisingly easy.

Her arena is littered with exploding barrels. You can place some at the door to her room before the fight. These barrels will ignite her, causing Mama to take fire damage over time (burn damage takes five minutes to kill her at 10 HP/second). You can also kill her without opening door using the crossbow if you hit every shot and you have full ammo.

If you are quick enough, you can grab the blue key from behind her, run and open the exit, then simply wait for the fire to kill her. You can also fight her from the exit hallway, provided you duck away when she prepares to attack. As with all bosses in DUSK except the final one, there is no need to kill Mama and you can avoid combat entirely by grabbing the key and running to the blue door, moving on to the next area.

Quotes

 * "What have you done?!" (On noticing the player)
 * "My daughters!" (On death)

Trivia

 * Her boss theme is | Murder Machine Inc., shared with Big John appearing in the level after.
 * The Cowgirls first appear as semiregular enemies starting in the following level, Erebus Reactor. This gives the impression that she was calling to them on death.
 * Visually speaking, the room after her arena is the first room to share the 'magitech' style that E2M6, M7, and M8 continue.
 * Mama has six times as much health as a Cowgirl and is visibly twice as large.