Bleeding Script Works only in Studio?

wait(3);

while true do

    if _G["bleeding"] == true then
        local blood_block = game.ServerStorage.Blood:Clone();

        local pos = game.Players.LocalPlayer.Character["Left Leg"].Position;
        blood_block.Parent = workspace;
        game.Players.LocalPlayer.Character.Humanoid:TakeDamage(1);
        blood_block.Position = pos;
        game.Debris:AddItem(blood_block, 4);

        if game.Players.LocalPlayer.Character.Humanoid.Health <= 0 then
            _G["bleeding"] = false;
        end

    end
    wait(0.5);
end

Why does this only work in studio, and not in-game from the roblox browser? Ever other script works?