Creatures mod by MirceaKitsune
Authors of media and source files:

MirceaKitsune, PilzAdam (LGPL):
  *.lua (source code)

MirceaKitsune (WTFPL):
  mobs_human.*
  mobs_anthro.*
  mobs_anthro_*.png

MirceaKitsune, Stuart Jones (WTFPL):
  mobs_human_*.png
  mobs_clothing_*.png

PavelS (WTFPL):
  mobs_deer.*
  mobs_dirt_monster.*
  mobs_stone_monster.*
  mobs_sand_monster.*
  mobs_snow_monster.*
  mobs_tree_monster.*
  mobs_rat.*
  mobs_sheep.*
  mobs_oerkki.*
  mobs_dungeon_master.*

ExeterDad (WTFPL):
  mobs_rabbit.*

legoluft, Independent.nu, qubodup, Gwes, Ogrebane, Stilgar, Charlotte Duckett, Fernando Carmona (PD, GPL, CC-BY):
  *.ogg (sounds)