local rounds = {
  ["heavy-ballista rounds"] = "hballista",
  ["light-ballista rounds"] = "lballista",
  ["fire-launcher rounds"]  = "firelauncher",
  ["heavy-cannon rounds"]   = "hcannon",
  ["medium-cannon rounds"]  = "mcannon",
  ["light-cannon rounds"]   = "lcannon",
}

local numbers = {
  ten  = 0, 

local numbers = {
  ten  = 10, nine = 9, eight = 8, seven = 7, six = 6,
  five = 5, four = 4, three = 3, two   = 2, one = 1,
  zero = 0,
}

local rounds = {
  ["heavy-ballista rounds"] = "hballista",
  ["light-ballista rounds"] = "lballista",
  ["fire-launcher rounds"]  = "firelauncher",
  ["heavy-cannon rounds"]   = "hcannon",
  ["medium-cannon rounds"]  = "mcannon",
  ["light-cannon rounds"]   = "lcannon",
}

local howmany = numbers["%1"]
local hits = numbers["%4"]

local weapon = "ship_" .. rounds["%2"]
local hits_var, shots_var = weapon .. "_hit, weapon .. "_shot"

SetVariable(hits_var, tonumber(GetVariable(hits_var)) + hits)
SetVariable(shots_var, tonumber(GetVariable(shots_var)) + howmany)

<triggers>
  <trigger
   enabled="y"
   match="Your ship fires (\w+) (.+) at (.+)\, and (\w+) land"
   regexp="y"
   send_to="12"
   sequence="110"
  >
  <send>

local words_to_numbers = {
  zero = 0,
  one = 1,
  two = 2,
  three = 3,
  four = 4,
  five = 5,
  six = 6,
  seven = 7,
  eight = 8,
  nine = 9,
  ten = 10
  }

local var_name = {

  ["heavy-ballista rounds"] = { 
    weapon_shot = "ship_hballista_shot",
    weapon_hit = "ship_hballista_shot"
    },

    ["light-ballista rounds"] = {
      weapon_shot = "ship_lballista_shot",
      weapon_hit = "ship_lballista_shot"
    },

    ["fire-launcher rounds"] = {
      weapon_shot = "ship_firelauncher_shot",
      weapon_hit = "ship_firelauncher_hit"
    },
    
    ["heavy-cannon rounds"] = {
      weapon_shot = "ship_hcannon_shot",
      weapon_hit = "ship_hcannon_hit"
    },
    
    ["medium-cannon rounds"] = {
      weapon_shot = "ship_mcannon_shot",
      weapon_hit = "ship_mcannon_hit"
    },
    
    ["light-cannon rounds"] = {
      weapon_shot = "ship_lcannon_shot",
      weapon_hit = "ship_lcannon_hit"
    },
}


local howmany = assert (words_to_numbers ["%1"], "Bad number fired: %1")
local hits = assert (words_to_numbers ["%4"], "Bad number hit: %4")
local t = assert (var_name ["%2"], "No match for: %2")

SetVariable (t.weapon_hit, tonumber (GetVariable (t.weapon_hit)) + hits)
SetVariable (t.weapon_shot, tonumber (GetVariable (t.weapon_shot)) + howmany) 

</send>
  </trigger>
</triggers>

BOOM! Your ship fires ten basic-cannon rounds at Exposed Plague, and six land.

Run-time error
World: SmaugFUSS
Immediate execution
[string "Trigger: "]:49: No match for: basic-cannon rounds
stack traceback:
        [C]: in function 'assert'
        [string "Trigger: "]:49: in main chunk

[AWAY][Mail][*][SPK](450hull SEdir SLOW SEwind 100%shld 1385, 594) You give the order to fire!
BOOM! Your ship fires ten basic-cannon rounds at Exposed Plague, and six land.
Run-time error
World: Materia Magica - Forral
Immediate execution
[string "Trigger: "]:72: bad argument #1 to 'GetVariable' (string expected, got nil)
stack traceback:
        [C]: in function 'GetVariable'
        [string "Trigger: "]:72: in main chunk
Exposed Plague's shields absorb the full force of the cannon.
Smiling Norba, the Sea Queen tells you, 'Yer gonna regret that! Arr!@#'

ingaverage
ingot
ship_firelauncher_hit
ship_firelauncher_shot
ship_harpoon_hit
ship_harpoon_shot
ship_hballista_hit
ship_hballista_shot
ship_lballista_hit
ship_lballista_shot
ship_hcannon_hit
ship_hcannon_shot
ship_lcannon_hit
ship_lcannon_shot
ship_mcannon_hit
ship_mcannon_shot

howmany = 0
hits = 0

if "%1" == "ten" then
howmany = 10
elseif "%1" == "nine" then
howmany = 9
elseif "%1" == "eight" then
howmany = 8
elseif "%1" == "seven" then
howmany = 7
elseif "%1" == "six" then
howmany = 6
elseif "%1" == "five" then
howmany = 5
elseif "%1" == "four" then
howmany = 4
elseif "%1" == "three" then
howmany = 3
elseif "%1" == "two" then
howmany = 2
elseif "%1" == "one" then
howmany = 1
elseif "%1" == "zero" then
howmany = 0
end

if "%4" == "ten" then
hits = 10
elseif "%4" == "nine" then
hits = 9
elseif "%4" == "eight" then
hits = 8
elseif "%4" == "seven" then
hits = 7
elseif "%4" == "six" then
hits = 6
elseif "%4" == "five" then
hits = 5
elseif "%4" == "four" then
hits = 4
elseif "%4" == "three" then
hits = 3
elseif "%4" == "two" then
hits = 2
elseif "%4" == "one" then
hits = 1
elseif "%4" == "zero" then
hits = 0
end

if "%2" == "heavy-ballista rounds" then
weapon_shot = "ship_hballista_shot"
weapon_hit = "ship_hballista_shot"
elseif "%2" == "light-ballista rounds" then
weapon_shot = "ship_lballista_shot"
weapon_hit = "ship_lballista_shot"
elseif "%2" == "fire-launcher rounds" then
weapon_shot = "ship_firelauncher_shot"
weapon_hit = "ship_firelauncher_hit"
elseif "%2" == "heavy-cannon rounds" then
weapon_shot = "ship_hcannon_shot"
weapon_hit = "ship_hcannon_hit"
elseif "%2" == "medium-cannon rounds" then
weapon_shot = "ship_mcannon_shot"
weapon_hit = "ship_mcannon_hit"
elseif "%2" == "light-cannon rounds" then
weapon_shot = "ship_lcannon_shot"
weapon_hit = "ship_lcannon_hit"
end

SetVariable(weapon_hit,tonumber(GetVariable(weapon_hit))+hits)
SetVariable(weapon_shot,tonumber(GetVariable(weapon_shot))+howmany)