1. MacDeath
  2. Machiavillain
  3. Mad Hacker
  4. Mad Scientist
  5. Magnum Opossum
  6. Mailer Daemon
  7. Main Square Parrot
  8. Maître Demon
  9. Major Buzzkill
  10. Major Disappointment
  11. Major Problem
  12. Malignant Tutor
  13. ManBearPig
  14. Margarine Fly
  15. Marital Artist
  16. Marquis de Sad
  17. Mascarpony
  18. Masqueraider
  19. Master Chef
  20. Master of Disaster
  21. Master of None
  22. Master of Puppies
  23. Material Ghoul
  24. Mathemagician
  25. Mathematical Supermodel
  26. Mathemortician
  27. Mathlete
  28. Maul Cop
  29. Maul Rat
  30. Maxwell's Demon
  31. Meddler of Honor
  32. Medieval Knieval
  33. Mediocrates
  34. Mediogre
  35. Medusa's Hairdresser
  36. Mega Pixel
  37. Meh-warrior
  38. Melee Archer
  39. Mental Hygienist
  40. Menthol Camel
  41. Meowntain Cat
  42. Merchant of Menace
  43. Merit Badger
  44. Metal Slug
  45. Methylated Spirit
  46. Methylated Spiritualist
  47. Metro Gnome
  48. Micromanager
  49. Midlife Crisis Negotiator
  50. Milestone Golem
  51. Milestone Guardian
  52. Millennium Bug
  53. Millennium Falcon
  54. Mimic Milestone
  55. Mind Boggler
  56. Mindless Consumer
  57. Mindsweeper
  58. Mine Sweeper
  59. Minitaur
  60. Minor Glitch
  61. Mis-Conductor
  62. Misanthropic Lycanthrope
  63. Misanthropologist
  64. Mischieftain
  65. Misfortune Teller
  66. Misguidance Counsellor
  67. Missing-In-Action Figure
  68. Mission Creep
  69. Misspellcaster
  70. Misunderstood Idealist
  71. Mixed Reviewer
  72. Mobile Anthill
  73. Moby Duck
  74. Mocker Spaniel
  75. Modest Mouse
  76. Moist Owlette
  77. Molar Bear
  78. Molotov Cockatrice
  79. Mona Lizard
  80. Monocled Penguin
  81. Monophobic Hermit
  82. Monorail Cat
  83. Monotonous Drone
  84. Monster Hangover
  85. Monster in Training
  86. Monster of Ceremonies
  87. Monster Superior
  88. Monster's Stunt Double
  89. Monster-in-Law
  90. Monsters' Rights Activist
  91. Monstrous Appetite
  92. Monterey Jackal
  93. Monty Python
  94. Mood Killer
  95. Moonswine
  96. Moosenger of Death
  97. Moosequito
  98. Morse Whisperer
  99. Mortal Frienemy
  100. Mortal Tomcat
  101. Mortal Wombat
  102. Mosh Pitbull
  103. Moss Cow
  104. Motivational Poser
  105. Motor Pike
  106. Motorcyclops
  107. Mouse of Ill Repute
  108. Mouseferatu
  109. Moving Target
  110. Mud Golem
  111. Mudslinger
  112. Muffin Man
  113. Multi-porpoise
  114. Multi-tusked Mammoth
  115. Multidexterous Millipede
  116. Murdersquito
  117. Murphy's In-Law
  118. Murphy's Lawmaker
  119. Music Pirate
  120. Mutating Algorithm