Acid Vats
Will: We had the ability to create lethal water a long time before we made past-GW.
Will: Originally, I was going to rebuild Pipeyard to include acidic tanks, but I couldn't find any good locations for them.
Will: It wasn't until I was working on Saint's GW that I realized the prospects of undoing the damage of Moon's collapse.
Will: Waterfront was already done a long time ago, but the idea of extending the reconstruction into GW gave me a place to use that acid-vat idea!