Mummichog become established on the Atlantic coast of Portugal and southwestern Spain, starting in the 1970s and some have now reached the western Mediterranean basin. There may also be introduced populations in Hawaii and the Philippines. As bait fish, mummichogs are sometimes released in freshwater habitats, where they can survive, and there have been reports of individuals in New Hampshire ponds, as well as the upper Ohio River and Beaver River. The mummichog is a common fish in coastal habitats such as salt marshes, muddy creeks, tidal channels, brackish estuaries, eelgrass or cordgrass beds, and sheltered shorelines. It can be found
Creature of Havoc to the rules given the story circumstances: damage to the creature (the player) is reduced by 1 STAMINA point due to its tough hide, while rolling a double on the dice when determining the player's attack strength will instantly kill an enemy. The player begins the adventure as the "creature of havoc" of the title, an unidentified, violent beast with no concept of who or where they are. Because the creature cannot make its own decisions, it is governed by instinct, and die rolls are initially used to determine which pages to turn to, rather than the player's own choice.