As Millennials​ age, they’re no longer hitting the center aisles for the sugary cereals of their childhood. As a result, cereal giants such as General Mills Inc. (GIS) and Kellogg Co. (K) have seen their sales take a hit, waging an innovation war in order to regain the interest of an increasingly health conscious consumer cohort.

While a majority of the packaged food leaders have announced plans to transition to healthier offerings, acquiring startups and cutting calories in products, another tactic has been to use buzz-worthy publicity campaigns. In that fashion, Minneapolis-based General Mills says it is now giving away 10,000 marshmallow-only Lucky Charms boxes in an online contest. (See also: Cereal Makers Grapple With World’s Obesity Crisis.)

Marshmallow Mania

Instead of appealing to Millennials' new health habits, this time General Mills hopes nostalgia will be enough to reignite a love for old-time favorite breakfast staples. This month, the company has released specially marked boxes of Lucky Charms with a code inside the box. Marshmallow enthusiasts can then enter the code at to see if they won a box. Lucky Charms’ latest campaign follows the success of its social media driven marshmallow-only cereal giveaway in 2015, when just 10 boxes were distributed.

“Fans of Lucky Charms are obsessed with our marshmallows,” said senior marketing manager Priscilla Zee. “We were overwhelmed with calls, e-mails and tweets last year, asking for a box of our Lucky Charms marshmallows. So this year we wanted to give them even more opportunities to win.” The offering, which General Mills calls “the unicorn of the cereal world,” contains more sugar per serving than a Snickers bar or a Twinkie.

In general, the new campaign demonstrates just how desperate packaged food makers are to reinvigorate sales. With strategies that veer toward opposite ends of the health spectrum, it is apparent General Mills and its peers are still struggling to figure out what its market wants. (See also: General Mills Makes Another Cereal Gluten-Free.)