When aliens came, they didn't come from Tartarus, like the ponies were expecting, but from under the sea, and magic couldn't stop them. Luckily our little ponies know something that can: Jaegers. They'll fight to stop The End, and they won't give up.
Great beasts from another dimension are invading Earth. Equestria itself is at stake, only the massive Jaegers, creations of the greatest Equine minds alive, can stop them.
Midsummer Night, a Mark-II Jaeger, finds itself in the inky depths of an unknown ocean after a botched brawl. Seems they may have got a bit more than they bargined for though...