Its not entirely clear what goes wrong with destroying the dungeon but something surely does, as the forest and ceiling thrum with multicolored energy, psychedelic hallucinations made real. Euclidean space twists and dissolves as the strange light reflects off the floor, giving way to a vision of reality that must be real, given that May can see it, but still is completely indescribable for several seconds.

The world returns to relative normalcy all at once, with May falling briefly in a dark room, knocking a robed individual over just as several voices finish the final syllable of a solemn chant. A jolt of strange electricity courses through her a moment later.

She didn't bring a big floodlight but she's never in a dungeon without a little one; she grabs it with quick practiced reflexes and clicks it on, while scrambling back to her feet.

It looks very much like she has dropped into the middle of a satanic ritual, as practiced by the least likely group of satanists imaginable. Most of them are wearing robes but that's about where there resemblance to each other stops - of the ones wearing the hoods down one looks like she could be in her first semester of college, just told off by a disgruntled professor, while another appears to be a sweet old lady who has inexplicably decided to scowl. The room itself is underground, the walls made of stone bricks. In the center of the floor is some sort of elaborate chalk diagram containing a small pile of ashes. Each individual has their own small diagram adjoining to the main one. May stands in one such smaller diagram.

"The hell!" exclaims the previous owner of May's diagram, having been knocked to the floor beside her.

"Where the fuck am I and what in the world are you doing?"

Well, four of the individuals seem to be leaving, one after some hesitation.

"Somewhere you didn't expect to be, I'd venture," says the old woman.

"Abrogate your claim, now!" says the man, who apparently has a switch blade he is going to threaten her with about this.

"Put the knife down, you're more likely to hurt yourself than me." The mushroom dungeon had little myconid monsters that ignored her because she is magical, but she's still wearing a normal amount of body armor for a dungeon, it doesn't do to be completely unprotected against something you don't expect when you're walking into a novel theme park of a hostile pocket dimension. "I don't know what you're talking about and I get way less cooperative when people are waving knives around."

"Oh I like her," comments the woman.

"Is this even legal?" asks the one remaining individual with their hood concealing their face.

"Well, one way to find out," replies the woman, gesturing with a snap at man with the knife.

The man's arm twitches, in a manner that muscles wouldn't ordinarily prefer, to throw the knife at May.

Only to be stopped in it's path by the sudden appearance, in a burst of yellow light, of a glowing young woman, clad in light scale armor, the switchblade bouncing harmlessly offer her sword.

"Well, that answers that." concludes the woman. 

Cloaked individual decides this is an appropriate time for him to vacate the premises.

"Who are you?" May asks.

"Lianelle of Kusheth,"

Knife man appears to be extremely nervous about this fact! The old woman just seems to think it's vaguely funny. 

"And... are you willing to explain to me what's going on?"

"You've summoned me to serve as your champion for the fight for the Spring Solomon," she replies, without taking her eyes off dagger guy.

"And if we imagine for the sake of argument that none of that helped me orient to the situation at all how would you elaborate on that?"

The old lady suppresses laughter so as not to interrupt this amazing conversation.

"Magic is real, every 25 years there is a tournament to determine who gets a very powerful magical gift. The only way to win is by being the last one alive."

"I did not volunteer to participate in a battle royale tournament. My magical powers are for saving people's lives, not murdering them over swag."

"Then abrogate your claim!"

"Doing so would kill you."

"How would it do that??"