You roll off Corona and try to collect yourself. It's only just starting to sink in that you were only a second or two away from... yeah. Not thinking about that right now. You rear up on your haunches and take a look through the window - the years of dirt have been joined by massive scorch and scratch marks, making it pretty much impossible to see through. Even the door has a couple of ominous-looking inward dents. The lab must be well and truly levelled. Corona sits up as well, dusting herself off. You can't make out a whole lot of her with only your little flashlight to see by, but you've picked up on the basic pattern from her sisters. She's tall - Princess Celestia tall - and where Auriga was nothing but purple and Boundless was nothing but green, Corona is a pleasant blue. Her mane is long and rough - you get the impression she's never even tried to wash or tidy it. She's dressed in a long, predominantly white coat, like something you'd expect to see a doctor wearing - one of Boundless' creations, maybe.
 
Corona turns to you and blinks in the light. "Oh, I'm s-so sorry. Are you okay?! The lock used electromagnets so I got the door open as soon as the power dropped but I wanted to warn you about the sterilization protocol and there wasn't any time-" She carries on in a steam of apologetic babble, and you take a slow breath. It's all a little bit overwhelming right now. Apparently her brain runs a few gears higher than her mouth, but at least she's more tolerable to listen to than that security system. Once you get a chance, you try to answer the question she started with - you're who knows how far deep underground, you got shot at a couple dozen times, and then you almost got turned into a small red smear. You're jittering with nerves and maybe trapped beneath a couple dozen tons of concrete if that blast brought the ceiling down, but apart from that, you're not doing too badly. How is she?
 
Corona rubs her forehooves together. "Fine! I'm fine. I mean, relatively speaking since I've been trapped in here for an entire day. Are you Boundless' friend? Is she okay? She said someone was with her. Is Auriga okay? She opened the outer door but then the turret drove her off. I hope she's okay. Ooh, hold on." She lights her horn, the glow intensifying until you can see the little room clearly. It's an office, cramped but well-furnished, with a comfortable-looking chair, a computer terminal, and a row of filing cabinets that looks to have been thoroughly rummaged through. Corona's 'labcoat' has plenty of pockets, all stuffed with rolls of paper and even the occasional folder, so it's not difficult to draw a connection there. Presumably this place belonged to whoever was in charge of the lab. You reassure Corona that her sisters were fine last time you saw them (a bit of a lie, sure, but the pair of you need to focus right now).
 
Immediate problems first. You need a way out. "I know! I tried to hack into the terminal but it locked me out and closed all the doors and-" You quickly touch a hoof to Corona's mouth before she can start rambling again. Speaking of doors, you ask, can she open this one back up? Corona sets her hooves, scrunching her muzzle in concentration as her magic once again takes hold of the door. It grinds open with painful slowness, obviously badly damaged, but it looks like her magic is up to the task. A wash of rancid smoke drifts in through the gap, forcing you to cover your mouth, but eventually there's enough room for the two of you to squeeze through.
 
The lab is a burnt-out husk, parts of the furniture still blazing brightly. If there was anything worth salvaging in here, it's gone now. Your fear about the roof coming down seems to have been half-right - there's room to move around, but the floor is littered with hefty concrete chunks and the ceiling has a whole lot of very ominous-looking holes and cracks, some of them still leaking dust. The barrels of toxic waste have disgorged their contents all over their side of the room - knowing your luck, the stuff's being carried in the smoke. You hurry back through as quickly as you can, Corona bringing up the rear. Now that the hard part's over all you need to do is follow the blood trail back and you're home free. About time - that smoke's making you feel woozy.
 
As you round the second corner down the corridor, reality decides to give you a firm reminder that it couldn't possibly be that easy. The trail suddenly terminates in a solid wall of crumbled concrete - the ceiling must have been weaker here, collapsing thanks to the shockwave of the lab going up. Immediately you start digging at it with your hooves - no way are you going to let yourself get trapped down here. All of a sudden you feel panic setting in - if there's no way out you'll starve to death, or choke to death on the smoke, or waste away in the radiation. You've seen what radiation sickness does to ponies; that's not something you'd inflict on yourself for all the caps in Equestria. You yell at Corona to help you dig, but she just stands there with her head canted like you're some kind of idiot.
 
"Um, why don't we just take the lift? Ooh, and whose blood is this? Is it yours? Did you get hurt? Is that why you're so scared?"
 
Wait, what? There's a *lift*?!
 
"Well, um, I found it earlier and it's broken down, but that's no problem. I've got wings, see?"
 
You stare blanky at her. She does indeed have wings. How fortunate.
 
Corona takes the lead, sheparding you back into the twisting corridors with her horn lighting the way. Sure enough, in what feels like the deepest bowels of the structure, there's an elevator. The car itself is long past functioning, but there's a hatch in the roof. Corona's magic makes short work of it, and she lifts you up into the shaft before clambering up through the hatch as well. It's a struggle for her, big as she is - it's lucky that the alicorns all have slim and elegant builds; if Corona was proportioned like a regular pony or covered in giant muscles like a lot of mutants, she'd never fit. Getting Boundless through would be out of the question.
 
Corona kneels down on the roof of the elevator, raising her wings. "Here, I'll carry you up." You nod and straddle her back - it's awkward in the low light, but you manage to get settled and take hold of her coat. She stands back up and takes a few experimental flaps. "I'm sorry if it's not very comfortable, there's not much room and I'm a bit tired and I've never had a stallion ride me before so actually never mind I'm sure we're both fine so here we go."
 
Your momentary mount takes off faster than you can say 'freudian slip', flying straight upward. You let yourself breathe a sigh of relief, resting your head on the mare's neck. Now that you're both on your way back to the surface, maybe that actually wasn't so bad. You're both in one piece, Corona already looted the lab so maybe this was all worth something, and now you can circle around to find the others and get Auriga on her hooves again. You even feel warm - maybe the lift connects straight to the outdoors. Sunlight would be welcome right now. Your ears twitch - wait, how can it be sunny if you hear lightning? The door at the top of the shaft is already open, and Corona quickly comes in to land. She immediately fluffs up her feathers and takes a few steps on the spot. "Ooh! This is nice."
 
You look up. You're not outside, but actually in a massive room of the power plant. Judging by the windows high up on the walls, you're at least at ground level. In the center of the room, ringed by catwalks and safety rails, is a ruined machine the size of a small house; a great mass of pipes and chambers and gears and crystals, caked with rust and looking about ready to collapse at any second. It hums ominously, every so often sending out jolts of colorful sparks. It's surrounded by barrels like the ones you saw before - dozens upon dozens of them. The atmosphere is rank, oppressive, pressing down on you maliciously as if the air itself is a moment away from seeping into you and unwinding you from the inside.
 
You scream at the top of your lungs for Corona to run. Of course - of course the elevator leads straight to the main reactor room! Why did you even think it would take you somewhere safe? To her credit, Corona doesn't argue. She has to know that you're not fed by radiation like she is. Her long strides let her set a decent pace while you simply cling on for dear life with three legs, fumbling for your last RadAway with the fourth. It's enough to just about keep you conscious, but not much more than that. You feel dizzy, your vision blurring at the edges. Your stomach feels like it's slowly filling with hot cement.
 
A minute later, clear of the radiation hotspot, Corona rounds a corner, and you see Boundless sit up in surprise at the entrance to the basement hatch. You crack a little smile at the scene - Auriga is halfway out of the hatch, flat on her stomach. The stubborn mare must have crawled all the way up all those stairs. Corona lets you down but you can't keep your balance. You stagger a little, then teeter on two hooves; Boundless is quick enough to catch you before you can fall flat on your face.
 
"Oh my stars, hon! Not you, too. What happened?"
 
You give Boundless a little smile, falling limp against her body. "Had an adventure," you murmur. You weren't dreaming earlier; Boundless is very warm and soft. Super comfortable. The perfect place to just... pass out. Yeah, now's a good time to do that.