In its 22nd year, Halloween Horror Nights is the juggernaut, churning out a new set of scares every year. Spooky music, lots of fog and a sense of uncertainty contribute to an overall feeling of trepidation.

The general mood at Busch Gardens in Tampa, on the other hand, is: Time to party! Most of the park’s roller coasters operate during the event and DJs keep music going. Even demented clowns were dancing by the end on a recent night.

Howl-O-Scream, celebrating its 13th year, seems more family-friendly. There were pre-teens in attendance opening weekend at Busch Gardens, where a general warning says that the event “contains intense adult content such as violence, gore and blood.” Halloween Horror Nights is not recommended for kids under 13.

During opening weekend, zombies waited for crowds to get off the tram. There was an impressive array of other wandering hordes, including undertakers, camouflaged bushes and people who looked completely normal but for the ghastly props that occasionally jumped to life.

“What we tried to do this year is put as much on the street as usual so guests can experience it as they walk through,” said Scott Swenson, director of creative services at Busch Gardens. “They are sort of lurking in the shadows all over the place.”

Howl-O-Scream keeps some houses around from year to year, with tweaks; two are new: Blood Asylum and Circus of Superstition 3-D.

In the gory Blood Asylum, a serial killer runs loose through an asylum for the criminally mad, with disturbing results. The floor vibrates in one section where a man is being electrocuted; bloody entrails make an appearance.

More visually appealing, at least from the outside, is Circus of Superstition 3-D. Colorful Christmas lights give the entry a festive feel, but inside, 13 superstitions await. Many are not too bad — who has ever had a nightmare over open umbrellas? — but the room full of clowns makes up for the less inspired areas.

In the middle of the pack of returning houses are Ultimate Gamble: Condemned, a run-down, vampire-infested casino that is navigable by the light of one flashlight per group and Nightshade Toy Factory: Mutation, full of toys that have been contaminated with nuclear waste.

Zombie Mortuary provides a fantastic narrative with ample moments of real fear. Zombies lurk, but even just the sets (including a mourning room and crematory) are scary on their own.

Nevermore, based on the work of gothic writer Edgar Allan Poe, was a standout (especially for this bookworm). The house has been updated in its second year, and it’s better than the Poe-themed offering that Universal had last year. One suffocating room actually feels like it’s closing in.

Howl-O-Scream also offers an individual experience called Alone, which costs $50 above the admission price for one person. We didn’t try it, but Anthony Armenia, an editorial associate for Orlando Attractions Magazine, went through it twice and described Alone as “intense.”

“Just having no one in front or behind you definitely gets your nerves going and blood pumping,” said Armenia, 17, of Tampa.

If the idea of spending an extra $50 is too frightening a proposition, rest assured. There are plenty of scares available for the price of admission.