Morty knows he shouldn't be screwing around with multidimensional shit. It's dangerous, it's impractical, it's blah blah blah. But it's a potential key to unlimited energy, how does nobody see that? He's built a dimensional siphon (it kind of looks like a cardboard box with a funnel and a TI-84 taped to it, but it damn well works), keyed in the dimensional coordinates to a random plane, and by God he's going to use it.
He flips the switch and waits for the energy bar to fill up.
It does! It fills up very rapidly. Then it explodes, along with the box. There's rather more smoke than there should be, and once the smoke clears someone is standing there.
"Oh dear," Morty says faintly.
The restaurant is in an old and pretty building, as advertised! Ariel holds the door theatrically.
They get a seat quickly; Wednesday's not exactly peak operation, and this isn't a big place. Ariel makes some conversation with an elderly Chinese waitress who apparently remembers her from when she was knee-high to a grasshopper &c.
The TV in the corner flashes a threatening red. "Warning! You are within! Fifty feet! Of a supervillain attack! Take cover as best you can! Help is on the way! Villain rating Ex! 2! En! 4! Codename: Firebrand!"
Most of the diners sigh and file towards a designated panic room in the back of the restaurant. Ariel, however, lights up. "Bella! D'you mind if I take this one, I'm deputized and all, I can totally take this! It's been, like, months since I got to thwart somebody!"
Bella is frozen for one and a half seconds, then shakes herself and says, "Tell me where to put bystanders and go for it."
"Oh, uh, good idea. If she's got hostages, you should flicker them into the restaurant's panic room, it's a good one. You can follow me in, I'll attract all the attention. Oh, do you have... costume preferences, or anything, or should I just make you all blurry?"
"Maaaybe, but it'd be a heavier-duty illusion than just a grey bodysuit or something. Especially with Grimesy's mental protection. Basically your options are spandex and blur, at the moment."
She nods, unfurls a swirling blue aura around herself, and flies out the door.
Bella follows her, flickering rather than walking, looking for anyone in harm's way and taking note with a look over her shoulder of the exact location of the panic room.
The villain notices Ariel and flinches. "You! Supergirl! If you move one inch closer I'll fry her face off!"
Ariel raises her hands placatingly. "Didn't know you had a hostage, I can't do shit about that, I won't come any closer. Thought this was one of those situations where I could helpfully beat the living hell out of you."
"Well- you can't!"
"Nope."
Bella flicks to just within range of the hostage and then puts them both in the panic room.
Firebrand blinks.
Ariel puts her through a window.
After some very loud crashing noises, the panic room's intercom blares "Threat over! Return to your business! Thank you, Storm Hammer!" There's some polite applause, and the diners file back into the restaurant.
Ariel comes in a few minutes later. "Sorry about the wait, I had to arrange a deposition and all that. It's- hey, are you okay?"
"I'll be fine. Seems I freak out about fire, but hey, not to the point of anybody getting killed."
"Well, I can try not to quake any earth around you either if you think that might be a problem. Otherwise, I'll just make sure Xan knows to go light on the napalm when you're in the area."
"I can probably dig it out of my head now I know it's there. It caught me off guard. Things usually aren't on fire."
"And I thank Mutant God for that every day. Though I'm sure it'd be a very interesting world if things usually were."
"There is not in fact a Mutant God. There's some gods, but invoking them is kind of risky, so facetiousness."