ComfyFactorio/modules/splice_double.lua

-- biters splice into two -- by mewmew

local Event = require 'utils.event'

local biter_fragmentation = {
    ['medium-biter'] = 'small-biter',
    ['big-biter'] = 'medium-biter',
    ['behemoth-biter'] = 'big-biter'
}

local function on_entity_died(event)
    if not event.entity.valid then
        return
    end
    if biter_fragmentation[event.entity.name] then
        local entity = event.entity
        for _ = 1, 2, 1 do
            local p = entity.surface.find_non_colliding_position(biter_fragmentation[entity.name], entity.position, 3, 0.5)
            if p then
                entity.surface.create_entity({name = biter_fragmentation[entity.name], position = p})
            end
        end
        return
    end
end

Event.add(defines.events.on_entity_died, on_entity_died)