Now this may come off as dumb but could potentially work for Good mill decks (yes they exist).

Can you use the R on Torn Hero if said Torn Hero in question is being targetted?

torn hero doesnt wait for a target. technically you have to respond with torn hero before your opponent specifies which card they intend to commit. the response window for torn hero, like many other "after .....plays....." abilities is at the colon of the ability.

stamp for ziepnir.

If my opponent plays an attack and responds with Manifest Destiny, can I redirect the target on Torn Hero, even if Torn Hero doesn't share a single symbol with the played attack ?

Of course mon p'*** Poupou

Yup. Torn Hero can even make Amy's Assistance commit it, or like Terrible Discovery. Even **Dan**'s First E: can be Torn Hero'd.

New question on torn hero vs. more machine than woman, if I use more machine than woman on an attack that is at 4 dmg can torn hero still react to make me commit it even though Moremachine wouldn't commit anything cause it didn't reduce to less than 1. I am assuming it can since it reacts to an ability played and more machine, while not always being able to commit, has the potential to commit.

I definitely think so. However, Torn Hero says, "commit this card instead. " If there is no committing going on - is it still possible to commit Hero instead?

Again Torn Hero reacts to the playing of the ability, before any of its effects take place. So with amy's assistance, even though your opponent may not commit an asset, you react before they decide. It is the same principle with more machine than woman. Because the ability can commit a card, then they can react with torn hero, bearing in mind that with MMTW if you do choose to commit a card after the reaction with torn hero, then your target will automatically be redirected to the now commited torn hero, and so it wont do anything.