What, you’ve never heard of Frute Brute and Fruity Yummy Mummy? To a certain population that grew up in the 1970s and ’80s, the return of these cult-favorite monster-themed cereals—in vintage form, no less—is bringing on a high on par with eating two bowls of sugar cereal while Saturday morning cartoons blare on the TV.

Halloween may be just one day, but it’s turned into a monster season for spending. Consumers dropped $6.9 billion on Halloween items in 2011, up from just $3.3 billion in 2005. Projected Halloween expenditures soared to $8 billion last year.

Most of that spending is on costumes, candy, and decorations. The Halloween period has also become a hot season for sales of certain spooky cereals. The New York Post noted in 2009 that October sales of Boo Berry, Franken Berry, and Count Chocula—all made by General Mills—are nearly double that of a more typical month.

Playing off the seasonal success of these cereals, General Mills announced in late summer that due to popular demand it would bring two obscure monster-themed cereals back to stores this fall: Fruity Yummy Mummy, which was only sold from 1987 to 1992, and Frute Brute. The latter, featuring a werewolf as a mascot, hasn’t been in stores since 1982, but has gained a cult following over the years, partly due to vintage boxes of “Fruit Brute” (its original spelling) making cameos in two Quentin Tarantino films, “Reservoir Dogs” and “Pulp Fiction.”

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Most thrilling of all (to some at least) is that all five cereals are available, exclusively this fall at Target, in boxes featuring their original characters, look, and design. The retro-look boxes started showing up in Target stores a week or so ago, causing some fans to burst with nostalgia-induced excitement. “Right there in Target, my childhood was on display!” one blogger wrote of spotting Count Chocula “in his definitive form,” as well as vintage images of Franken Berry and the rest of the gang. “It was like I was standing in front of the Mona Lisa in awe.”

“These retro boxes do NOT disappoint,” another blogger commented. “They really do look like the genuine article. Besides, purchasing an original, vintage collection of these empty boxes would run you well over a grand these days, so being able to get the complete retro Monster Cereal set in such pristine condition for the cost of a regular cereal box is one hell of a nice Halloween season treat for us all.”

Some Monster Cereal fans know so much about these cereals that it’s, well, kinda scary. When the General Mills blog first announced the spooky seasonal promotion period, the comments section turned into a discussion about how the current iterations of these cereals are different—and inferior—compared to the cereals in the ’70s and ’80s. “The new recipes are indeed abominations,” one commenter weighed in. “Not even close to their original taste.”

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Another commenter educated readers with a spoonful of cereal jargon:

The original recipe of Count Chocula had only one type of marbit — a light cocoa-flavored one. The cereal has had many different marbit permutations over the years, including the addition of “ghost marshmallows” and the like. The cereal was lighter as well, not the current dark cocoa flavor, and it was not shellacked with HFCC, like the current incarnation.

The Minneapolis Star Tribune noted, “The monster cereals contain 9 grams of sugar per serving — 40 percent less than in 2007 and in line with some flavored iterations of Cheerios.” Ari Zainudden, General Mills marketing manager, admitted that the cereals have changed, explaining, “We chose the current flavors of Fruity Yummy Mummy and Frute Brute to be as close as possible to the original flavors while taking into consideration consumers’ preferences. Consumers can get a taste for what these cereals were like when they were originally on shelves.”

Whether these cereals have the original taste (and sugar content) or not, they’re likely to be hits while they’re displayed in stores. This is not only because Gen Xers will want to relive their childhoods a little bit, and perhaps share their old Saturday morning snacks with their own kids, but also because consumers are prone to snatching up almost anything when they’re aware it’s only available for a brief spell. Hence the success—and continued reappearance—of seasonal and limited-time-only fast food items like McDonald’s McRib and the Shamrock Shake.

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“It’s the idea of scarcity,” said Vlad Griskevicius, a University of Minnesota’s Carlson School of Management professor, told the Star Tribune. “Humans are wired to want things they can’t have.”

General Mills doesn’t have big plans to market its retro cereal line, so don’t expect to see many (if any) commercials for the products. But plenty of YouTube users have uploaded the original ads, including this one featuring Count Chocula, Franken Berry, and Fruit Brute:

[youtube=http://www.youtube.com/watch?v=aR3vQbuqej4]