I don't know what Timbre was expecting. I mean, he had no plans for his aims beyond mass killing and chaos, and he didn't even do a particularly good job. If he had chosen a month with no arcane gales predicted, for example he could have had more time. He also should have chosen a higher populated area. The Graveyard District is perfect for this due to the high population, and he literally had a day there to do whatever he wanted, but he focused his efforts on Mossgarden instead. Maybe it was to spite Althea, but his plan didn't even work.
If I was to make a plan that benefitted me but hurt untold innocents, say, collapsing the Wardenspire, I would be so much more efficient. Say, secretly setting dynamite across the Wardenspire itself at structurally key locations over a period of months.
Now, how would I acquire the dynamite? Simple, I'd put a stake into the mining business (I know the Mining district is owned by the DIA, but I could buy stake in something in another city down here if I need to), then over a few months have a small amount of dynamite shipped to me with other supplies. This requires 1 worker I can trust. I believe I can manage that, there's a stage hand I have who would be perfect for it.
After the dynamite arrives, I would place them by summoning imps. These imps would paint the dynamite to camouflage it, then bolt them to the Wardenspire while turning themselves invisible. This would be done concurrently with the dynamite arriving, so a matter of months at most.
Following this, I would have an imp (or series of imps) lie a fuse between them all (which I would also need shipped to me, I suppose), leading down the Wardenspire to a central location. This would only be able to be done immediately before the blast, as I worry that the fuse would be more discoverable than the painted dynamite.
Then, it's just a matter of lighting a match. Destroying the Wardenspire would certainly be a way to get rid of the Ivoryclads. And, if I place the dynamite correctly, I can control the direction the tower falls in. The Graveyard District would probably be the right choice, with luck I can bury Bones Malone so deeply he can never get out. As a plan, it would take a while, but it would work.
Though everyone would hate me here forever, so I'd need an exit strategy. Frankly, I don't know where I'd go, pretty much anyone would be willing to turn in someone like that, and I don't have any real connections outside of the city. I suppose I could barter with Fierna, but I really don't want to have to negotiate with hell again.
Besides, of course, it would involve the mass killing of innocents. That's a rule of mine I don't want to break. I can't do this, I won't do this, doing this would destroy me. Obviously.
I mean I suppose I could set it all up and then threaten to do it to gain political power, but I can't believe anyone would take that well. Besides, I try not to make threats I can't act on.