function blow(hit)
    if (hit.Parent == nil) then return end -- happens when bullet hits sword

    local humanoid = hit.Parent:findFirstChild("Humanoid")
    local vCharacter = Tool.Parent
    local vPlayer = game.Players:playerFromCharacter(vCharacter)
    local hum = vCharacter:findFirstChild("Humanoid") -- non-nil if tool held by a character
    if humanoid~=nil and humanoid ~= hum and hum ~= nil then
        -- final check, make sure sword is in-hand

        local right_arm = vCharacter:FindFirstChild("Right Arm")
        if (right_arm ~= nil) then
            local joint = right_arm:FindFirstChild("RightGrip")
            if (joint ~= nil and (joint.Part0 == sword or joint.Part1 == sword)) then
                tagHumanoid(humanoid, vPlayer)
                if humanoid.TeamColor==BrickColor.new("Bright red") or humanoid.TeamColor==BrickColor.new("Bright blue") then return end
                else
                humanoid:TakeDamage(damage)
                wait(1)
                untagHumanoid(humanoid)
            end
        end


    end
end