Hmm...undead are enemies....undead seeks to seize a whole island....Bilgewater is in Chaos....Kindred can delay deaths...
So far all arrows point to Kindred. There can really be no other suspects. It kinda painfully obvious.
LANWhale1 votesKindred can delay deaths
They sadly do not have control over when people die. Nor can they delay death. As well, as some one else stated before, who said that the thing that saves Bilgewater is going to be a person. For all we know it could be death it self that "saves" Bilgewater. And last time I checked Kindred is not death but the one who takes your soul.
As 
has mentioned over many times death is a liberation.
So far all arrows point to Kindred.
I see what you did there.
GenoXx1 votesum...Yeah they do? They delayed Magga's death in "a Good death." And they do influence people's deaths. Not sure how much u read.....but they choose whether some one dies brutally or more accepting.
This can very well happen with Bilgewater. In this case i feel like Kindred's reason to delay so many deaths would be because the offenders are those who defy death. Having Bilgewater turn into another Shadow Isles wouldn't be the best thing to happen to Runeterra
LANWhale1 votesI did read the Magga's death and I read Kindred's lore as well. The thing is they don't choose when you die, as far as i could tell, but rather only offer your way out. While yes Magga chose Lamb's arrow something that is key to point out that since she chose the peaceful way out that never dictates that they die on the spot. Had she chosen Wolf she may have died on that spot. So i'm not sure if its something that i over looked or something but i would be happy to know why.
Also, Kindred would perfectly balance out the Harrowing. They do not obey common rules of physics, they can be every where and no where at the same time. Which means that the Harrowing is completely useless, since in their lore she can shoot multiple arrows and they will all find their target. In other words it would pan out as such:
The black mist comes, its starts to kill people, Kindred is like nope and fires her arrows and they all find their mark and no one gets taken to the Shadow Isles.
What i'm saying is she is too good of an answer. If perhaps she had to obey some rules of physics then yes she would be the immediate answer but since she doesn't, this may not be that amazing of a Shadow Isles.
Ebonmaw Dragon1 votesThey sadly do not have control over when people die. Nor can they delay death.
I guess that the Ultimate of Lamb kills everyone then.
LANWhale1 votesNow see that would make sense but sadly gameplay=/=lore. Therefore her Ult is not something she can do in lore.