Doctor Ludvig Maxis (sometimes called Maxis) is a scientist who was part of the project known as "Der Riese." The player can find out about him after activating hidden radios. His team was responsible for creating the Hellhounds and Zombies. He was the leader of Group 935. Maxis never physically appears in game.

Doctor Maxis worked with his assistant, Edward Richtofen, at the Der Riese facility near Breslau. He created the Zombies and the Teleporters. He created the Ray Gun based on plans seized at Shi No Numa. It is assumed by Richtofen that he created the Thundergun and hid it from him, but as danger is seen written in Russian on the side of the gun, it could be possible that it was created at the cosmodrome in Ascension. As the experiments on Der Riese continued, Maxis became worried about Richtofen. He correctly believed Richtofen was becoming a threat to the Maxis' and his daughter's lives. Maxis was also growing attracted to Sophia, who returned the attraction, which distracted him from his work. Richtofen believed he was progressing too slowly and was taking too long to mass-produce the DG-2 as promised, so he conspired against him.

Doctor Maxis was working on an experiment with his assistant Edward that involved his daughter's pregnant dog named Fluffy. He attempted to teleport Fluffy, but when he did, the plan failed. Fluffy was teleported, but not to the mainframe. She teleported back inside the Teleporter from an electrical force, most probably the ball of electricity players see Hellhounds spawn from. Maxis demanded the door to be opened, but Edward refused. When they finally opened the door, Fluffy had transformed into a Hellhound. Samantha comes running into the room, asking her father what he had done with her dog. The Hellhound begins to attack, destroying the room. This caused chaos, and as Maxis tried to calm and reassure his daughter, Richtofen exits and locks the door behind him, trapping Maxis and Samantha with the raging Hellhound. Richtofen says "Goodbye, Dr. Maxis", and activates the teleporter, teleporting Dr. Maxis, Samantha and Fluffy. Because Fluffy was pregnant before becoming a Hellhound, she had pups, which explains why there are so many Hellhounds. Dr. Maxis was killed while Samantha survived, possibly due to the experimentation done on her by Richtofen. It would appear she specifically wants to kill Richtofen to avenge her father.

Now for some random facts:

  • In Der Riese, outside the room above the tunnel near Teleporter C there is a sign saying "L. Maxis M.D."(Quick Revive Room)
  • On the Black Ops computer he claims that Samantha's bear is watching him, and also that "Richtofen's Latest Creation" (The Monkey Bomb) shrieks when set on fire, although he also says that this may be an effect of the 115 on his mind.
  • As first mentioned in a radio message in Shi No Numa, an American says his name but he gets cut off by static so many people originally thought his name was just "Doctor Max".