This game was created a long time ago - either by Charlie himself, or it is some sort of "legacy" from his uncle Jack.
Night Crawlers is spelled "Nyte Kroolers" by Charlie, hinting at his illiteracy.
Charlie also develops a "Nyte Kroolers Rools" book, but those rules are not shown to the viewers.
- In preparation for Frank's intervention, Dennis asks Charlie to write Frank a letter letting him know the ways that his addictions have hurt Charlie. He puts at the top of his list "When was the last time we played Night Crawlers together, Frank?" Dennis, obviously, wants to know what Night Crawlers is, but Charlie is a little reluctant to give the details of the game, beyond saying that it is "What it sounds like." Later, in the actual intervention (which goes as well as you'd expect), Charlie does ask Frank "Why do we never play Night Crawlers?" When Dee asks what it is, Dennis responds that it's a game "where they crawl around like worms", which Charlie denies, but Frank confirms. ("The Gang Gives Frank an Intervention")
- Schmitty mentions that Charlie used to be his roomate, and how Charlie used to try and get him to play "lame games" like Night Crawlers. When Frank says that they play it "all the time", Schmitty asks him if he thinks it would be better to use blankets as "the dirt" or maybe "a force field, or a roaming base." Charlie is not impressed by his suggestions, but Frank agrees with Schmitty. ("The Gang Gets a New Member")
- As part of his fantasy sequence in which Charlie imagines marrying and starting a family with The Waitress, we see Charlie teaching their kids Night Crawlers (with a chart labelled "Nite Kroller Roolz") ("The Gang Saves the Day")
- Charlie describes the rules of the game to Dee, Dennis, and Mac when they are quarantined together in Paddy's men's room. In particular, he mentions going under the bed to "mine minerals". ("The Gang Gets Quarantined")
- The beginning of Night Crawlers is shown to the viewers where at the end of a long, jam-packed day, Charlie proposes to Frank that instead of going to sleep, they could play "one quick game of Night Crawlers". Frank accepts the proposal and the introduction of the game is shown from Frank's perspective. The introduction entails Charlie turning off the light and saying, "Darkness falls." He then wraps a blanket round his head and says, "And magic stirs!" Charlie then proceeds to throw the blanket over Frank whilst saying, "As we become the creatures of the night!" ("Being Frank")
- Probably, Charlie's "going into the crevice"-thing is somehow related with the Night Crawlers.
("How Mac Got Fat")
|—||“What is Night Crawlers?”|
|“It’s a game where they crawl around in nigh- in the night like worms.”||—|
|—||“I never said that… !”|
|“Yeah, well, that’s what it is…”||—|
|—||“Intervention! Intervention! Is nothing private, Frank? Jesus… !”|
- Frank: We play Night Crawlers all the time… !
- Schmitty: You do?
- Charlie: Well, Frank enjoys those games VERY MUCH, so…
- Schmitty: Oh, oh… Correct me if I’m wrong, but to make Night Crawlers a little bit better, you should use blankets, right?
- Frank: They could be the dirt!
- Schmitty: Exactly. You could use it as a force field or as a roaming base.
- Frank: Oh my God… ! It’s a great idea.
- Schmitty: Thank you!
- Charlie: Yeah… It’s NOT a good idea though, because you wouldn't- it’s an imagination-based game.
- Schmitty: No, it’s still imagination-based.