(PhD) Night-time scene. (PhD) The streets are mean. (PhD) The things I have seen. (PhD), the good, the bad, and the in-between. When you dive to prone, you are surely gonna own, PhD (Flopper)! When you dive to prone, it's gonna shake ya to the bone, all the zombies gonna groan, 'cause of PhD! (PHD) The feelin's growing strong. (PhD) So right that it feels wrong. (PhD) Like the chorus of a song. (PhD) Not short but not too long. Slap your body to the floor, everybody needs some more, of your lovin', your explosive lovin'. When you dive to prone, it's gonna shake ya to the bone, all the zombies gonna groan, cause of PhD! (PhD) (Flopper)! Damn straight.
- Ascension - Near the Lunar Lander "D" (where Frag Grenades are) and close to one of the zombie barriers.
- Call of the Dead - Inside the lighthouse, above the room where our heros are trapped behind a vault door.
- Shangri-La - Randomly spawns in the mines. Changes places with Stamin-Up, Deadshot Daiquiri, and Double Tap Root Beer.
- Die Rise - Can be seen on one of the floors when falling down the Elevator. It is an unobtainable perk.
- It is not actually a vending machine. Instead, it fills a cup placed under the nozzle.
- According to the players, PhD Flopper taste like Prunes and Chemicals.
- Takeo is allergic to prunes, making this his least favorite perk
- In the Die Rise map on Black Ops 2, PhD Flopper is secretly located on the 3rd level when going down the broken cargo elevator (at the beginning). It is physicaly impossible for the player to get to it because there is an invisible barrier around it. It is easier to see this perk machine when going into theater mode going on free camera.
- PhD Flopper makes it return into Black Ops 2 Zombies, in the map Mob of the Dead. As well as appearing by the docks, it is available for purchase in Cell Block, Grief for 2000 points.
- It is a play on the soda Dr. Pepper.