function Mod:onSpikesInit()

	local room = game:GetRoom()
	local grides = room:GetGridSize()
	-- local seed = game:GetSeeds():GetStartSeed()
	local backdrop = room:GetBackdropType()

	for j=1, grides do
		local gridEnt = room:GetGridEntity(j)
		if gridEnt then
			if gridEnt:ToSpikes() then
				-- if gridEnt.Type == GridEntityType.GRID_SPIKES
				-- or gridEnt.Type == GridEntityType.GRID_SPIKESONOFF then
				if backdrop == 6 then
					-- replace the sprite/spritesheet
					gridEnt:GetSprite():ReplaceSpritesheet(0, "gfx/grid/custom/grid_spikes_flooded.png")
					gridEnt:GetSprite():LoadGraphics()
				end
			end
		end
	end
end

Spikes:AddCallback(ModCallbacks.MC_PRE_ROOM_ENTITY_SPAWN, Mod.onSpikesInit)