CommonFun.calcBuff_7720
function CommonFun.calcBuff_7720(srcUser, targetUser, a, b, c, d, lv)
  if srcUser == nil or targetUser == nil then
    return 0
  end
  local Luk = srcUser:GetProperty("Luk")
  local CriDamPer = srcUser:GetProperty("CriDamPer")
  local CriDefPer = targetUser:GetProperty("CriDefPer")
  local DamSpike = srcUser:GetProperty("DamSpike_PEN")
  local RefineDamReduc = targetUser:GetProperty("RefineDamReduc")
  local DamIncrease = srcUser:GetProperty("DamIncrease")
  local skilllv = srcUser:GetLernedSkillLevel(2428_:NOVA_EXPLOSION)
  local Value = srcUser:GetGemValue(193121_NOVA_EXPLOSION_S_HP_LOSS_DMG_PERCENTAGE)
  local A = -(Luk * (1.5 + CriDamPer - CriDefPer)) * skilllv * a * (1 + Value / 100000)
  local AttrFunction = srcUser:GetProperty("AttrFunction")
  local bitfunc = CommonFun.getBits(AttrFunction)
  if (targetUser.boss or targetUser.mini or targetUser.changelinepunish) and (targetUser.zoneType == 1 or targetUser.zoneType == 22) and targetUser.noPunishBoss == false and bitfunc[CommonFun.AttrFunction.JustInViceZone] == 1 and targetUser.isBossFromBranch == false then
    A = 0
  end
  if targetUser.boss and targetUser.zoneType == 22 and CommonFun.CheckStormBossMiss(targetUser, srcUser) then
    A = 0
  end
  if targetUser:GetNpcID() == 30043_YEAR or targetUser:GetNpcID() == 280303_WILDNESS_SPIRIT_BEAST or targetUser:GetNpcID() == 56008_GOMORA or targetUser:GetNpcID() == 56009_BALTAN or targetUser:GetNpcID() == 56010_GOLZA or targetUser:GetNpcID() == 56011_BEMSTAR or targetUser:GetNpcID() == 56012_ELEKING or targetUser:GetNpcID() == 56013_KING_JOE then
    A = -1
  end
  if targetUser:DamageAlways1() then
    A = -1
  end
  if 0 < A then
    A = 0
  end
  return A
end