Possible new amumu build?

So this new one shot bulid going around for mid laners like leblanc and ahri, where you build hextech gunblade and lich bane, would that be good on amumu? I mean if you think about it amumu q in and normally autos and e's, so the lich bane would proc and the gunblade slow would keep them in his w for longer, and if you build a thornmail, you would heal from it because of the hextech gunblade. I feel like this would be a great build but cant play right now because I am currently very busy with school. Could someone test this out and let me know? I know I'm a bronze noob, but who caresssss that's why I'm asking questions lol. Thanks if you do.