startup.lua

mod = peripheral.wrap('back')
mod.open(15)
delay = 0.001
x = 2
cool = 0

z2 = {'-', ''}
while true do
    a, b, c, d, payload = os.pullEvent('modem_message')

    if payload == 'Arrow' then
        cool = cool + 0.2
        x = math.random(2,3)
        x2 = math.random(0,9)
        z = math.random(0,3)
       -- y = math.random(0,2)
        s = math.random(1,2)
        sleep(delay)
        commands.summon('Arrow ~2 ~1 ~ {damage:10,Motion:['..x..'.'..x2..',0.0,'..z2[s]..'0.'..z..']}')

        if cool > 15 then
            sleep(3)
            cool = 0
            commands.kill('@e[type=Arrow]')
        end

    else
        cool = 0
        --commands.kill('@e[type=Arrow]')

    end

    sleep(0.01)

end