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