From a news in weibo. Apparently I don't had the source where this is found aside from discord where it is posted.

I do wonder how submarines work in this game.

if i had to guess, i'd say they work like MAP attacks in SRW, weakening and maybe debuffing enemies.

The reason why the dev add her to the game: to help protecc destroyers

This image is stitched together from the 3 pics on weibo because for whatever reason this pic (and I-9's) is seperate into 3 images instead of 1. Maybe is size limitation on weibo, I dunno

A loli that sank a lolicon...

a sub in AL? hmmm I wonder how it works. well I can't wait.

Luke_1 said:

a sub in AL? hmmm I wonder how it works. well I can't wait.

Based on official sources, Submarines are support units they can attack enemy nodes or be "summon" in battle.

They had range how far they can attack or support as well as how long they can remain underwater.

lol
https://weibo.com/5770760941/GhPg2hUaA?type=comment#_rnd1527736760321
this is the source, but it's broken in 3 pieces. That image up there is something I made for the Discord announcement thread so you'd have a full image instead of slices