"Or both, I would not object to both."

"You may have both," says the Yvette-puddle, bubbling a little with amusement. "Hm. Let me give you options, that seems to be the way things are done here."

There's a pause, then: he is offered some options! He may have one of three choices. His teleport/dash can leave a ghostly after-image that will briefly trick enemies into thinking he'd never left, his sword can draw enemies towards him when he does this specific special action, or his blood magic cast can take on a slow moving, gravity warping effect that draws enemies towards the center.

"I think I can only do one for now, unless you have any spare stars available for me to eat."

"I think I'll what do you mean any spare stars?"

".... It's not as bad as it sounds. When I'm actually eating them, I only pick the ones with dead systems. Usually the unstable ones that were going to explode anyway, since I don't even know what I'd do with a whole star's mass. And most of the time I just siphon off what the star's already giving off. Basically soaking up sunlight? Except also heat and radiation."

"I think my mostly theoretical knowledge of stars is not up to par so instead I will just pick the gravity effect."

"Here you go." Gravity effect! "And the stars that I ate were giant balls of super-hot plasma, not, uh, whatever thing may be going on in this world with them. It's fine, really!"

"My thanks, Lady Yvette."

And three round holes open up on the floor of the temple floating in the middle of the starry void, smoky darkness leaking from each of them.

"You're welcome. And thank you for the doors that don't bite, Chaos!"

Well, she has no idea which door is the one Zagreus wants, so she'll just bundle up her puddle into a starry blob, and hop onto his shoulder. The one with the skulls. Actually, she can just go into the skulls to hang out, and be nice and unobtrusive. Maybe this is a bit gross, but her sense of what is and isn't gross is incredibly skewed, since she spent a lot of her early time as whatever-she-is throwing up and bleeding starscapes out from underneath her fingernails. And she can clean them of any leftover organic bits if they're not clean. But they're fine, right, he wouldn't be wearing really gross skulls on his shoulder everywhere he goes, right? ... Right?

No organic bits on or in the skulls, no, sir.

Zagreus looks at the three portals and decides on one of them seemingly at random, then in he goes.

They travel through a quick void, and Zagreus lands on one knee in a dark chamber of stone sectioned off from what appears to be moving darkness, with pinpricks of light from small crude buildings visible in the distance. Pillars of stone and various vases adorn the place, but it's eerily empty.

Until bells like death knolls start sounding.

Which causes Zagreus to immediately perk up and get to his feet.

She has no idea what that means! That's a bit intimidating, she's glad she decided to tuck herself away in the skulls on his shoulder. She reminds herself that she is a scary eldritch abomination from beyond the veil of the world, and there is no reason at all for her to be intimidated by some bells. Mhm. No reason at all. Also she's not hiding, she's neatly tucked away. Yes. That is what's happening here.

After a couple of seconds, another young man appears. His hair is silver and his eyes are gold, but the most notable thing about him is the enormous scythe he has attached to his back. His chiton is dark purple, held in place by various skull—and wings-themed pieces of jewellery, and has a hood which he has pulled up above his head. Despite this, his right pec, shoulder, and arm are left uncovered. He has leg guards similar to Zagreus's, and is also barefoot, although his feet do not look like they are made of lava.

"Than!"

"Hello, Zagreus," says the young man. Then he fixes his gaze onto Zagreus's shoulder. "And who's that with you?"

"Yvette, hi," says the blob of night tucked away on his shoulder, poking a little bit of starscape out from the skulls. "Nice to meet you," she adds, a little shyly. Look, she's intimidated, okay, he has a large scythe and his arrival is announced by a doom bell, he is intimidating.

"I am Thanatos," he says, simply. "A pleasure to meet you," although it sure doesn't sound it, with the monotone he uses to talk.

She doesn't particularly mind the monotone, actually. Thanatos, Thanatos, she has no idea what he's the Greek deity of, but the name sounds ominous? Actually maybe she should just look at him instead of being a blob of starscape.

A white-gold iris forms and glows from within one of the skulls' eye sockets on Zagreus's shoulder, and looks at Thanatos.

"Oh. The god of death," she says, thoughtfully. "Though more of a merciful relocation to the Underworld than just making them stop. You must be very busy."

"Yes, particularly with the war the mortals seem to be having at the moment. Not that any of this ever occurred to a certain cousin of mine."

"Hey, come on, Than..."

“Is it just you? For all mortals, everywhere in the world? Oh it is, that’s terrible. What happens when an industrial revolution hits. What if you want a vacation! Do you just leave everybody awkwardly in agonizing mid death limbo whenever you go on a water break?!”

"Time tends to be on my side," he replies, cryptically enough.

"Wait, I don't suppose I could get in on that? That would make these escape attempts way easier."

"No."