I'm in the mood to talk Sea Change AU
I never actually outlined this one outside of conversations with @argusden, but I'm going to do that now because I rewatched KOTM and PacRim and looked at a whole bunch of sad Upraisin things and I have Emotions.
So there are a few divergences here in that Mako and Raleigh were never expected to sit out the Double Event, BabyTachi aka Dave was born sans umbilical cord like a dolphin (which would have made more sense anyway imo) and Lady Danger being nuclear isn't special (and she's called Lady Danger rather than the other thing because it sounds cool and isn't racist).
Cherno Alpha and Crimson Typhoon make it out of the Double Event mostly unscathed, but Lady Danger and Striker Eureka are destroyed. Herc's escape pod makes it to the surface, but Mako, Raleigh and Chuck are sadly unaccounted for.
Pitfall is now in the hands of the Wei Tangs and Kaidenovskys, who are all perfectly able to complete the mission. Technically.
Unfortunately, the PPDC doesn't have all the information they need. Fortunately, they have a mostly-competent science team off to drift with a kaiju and get that information. Unfortunately, Dave is hungry, and promptly fucks off back to the Anteverse after a nice meal of overconfident dipshits. This is, obviously, not ideal.
Typhoon nukes itself in place of Striker, and Cherno hits the Breach. Sadly, with no-one to pass on the information they need to get in, they don't make it through. I'm still unsure of whether or not to let our favourite Russians live, but either way they haven't had the best day.
So the Breach remains open, and humanity is fucked. Except...nothing else is coming through.
So the Shatterdome remains open and monitoring the Breach, with an increasing sense of dread. Stacker adopts another kid (Amara), Herc starts rebuilding the Jaeger program, Karla takes over the science division and gets an intern (Madison Russell), and they mourn their losses.
On the one-year anniversary of Pitfall, there is movement in the Breach. Just for a moment, and then it's gone. No monster rises from the waves. It's dismissed as a false alarm.
And that's when shit gets weird.
Somehow, Raleigh Becket, Mako Mori, Chuck Hansen, Newton Geiszler, and Hermann Gottlieb are alive and well.
Nothing could survive what they went through.
At least, nothing human...