PORTLAND — In real life, Eamon Lovejoy of South Portland is a little boy.

But on Sunday the 2 1/2-year-old was the mighty Avenger, Thor, fresh from the pages of a Marvel Comics book. Dressed in a cape and winged helmet, Eamon scanned the booths for masked super-villains at the Coast City Comicon, a comics and fantasy entertainment convention.

“I thought this would be a fun father and son activity,” said his father, Josh Lovejoy, toting his son’s action hero-decorated diaper bag.

The Lovejoys were among more than 750 people, some of them in costume like Eamon, who had already shown up for the three-day event by Sunday morning. With another day and night of activities ahead, the organizers were already proclaiming it a success.

“We doubled what we expected the first day,” said Tristan Gallagher.

Gallagher and his staff at Coast City Comics organized the event.

The gathering featured an eclectic mix of comic book creators, tattoo artists, guerilla movie producers, special effects artists, video and fantasy game enthusiasts and cryptozoologists, who study animal legends such as the Loch Ness Monster, Big Foot and Maine’s own Cassie the Casco Bay Sea Monster.

The convention drew all ages, most of them male.

On the exhibition floor, special effects artist Eric Anderson of Portland presided over a table heaped high with grizzly looking silicone objects, such as fake amputated fingers, ears and noses.

“Some people like to bake a finger in a cake to surprise the family,” said Anderson, who recently made the switch to bloody special effects after being laid off after years in information technology.

Anderson’s creations have appeared in a number of Maine-produced independent films, including those by actor and producer Bill McLean and his Freight Train Films in Monmouth. McLean was on hand to take part in a panel discussion on guerilla movie production, which involves shooting low- or no-budget movies in locations where the filmmakers often lack permission from the property owner.

Yarmouth High School graduate Mort Todd, a writer, editor and artist at Marvel Comics, displayed his superhero-themed depictions of such local icons as the Portland Head Light and the Time and Temperature building.

Conventioneers looked on as Portland tattoo artist Chris Dingwell showed off his fine art skills with acrylics on canvas along with other local artists.

Dingwell said artists don’t get to work in front of an audience very often.

“Almost no one gets to watch us,” he said.

Ross Kearney, a co-organizer of the convention, said he and his fellow organizers are pleased with the turnout and even managed to break even.

Kearney said that is a sign of the untapped potential of the Maine comics and fantasy entertainment market. Kearney and the others are already planning a second convention.

“We have already booked two major guests,” said Kearney.