Whether you prefer TCGPlayer, CoolStuffInc, CardKingdom, or your local game store, youll probably find some inventions lying around
You already know which player you want to be, so make sure you are piloting a deck that helps you get there
Now, I have in the past advocated for the fact that I don't think Theoden is as bad as people think he is, most notably in this old blog post: wardenofarnor.wordpress.com However it is important to point out that there is a wide gulf between "not as bad as people think he is" and "good compared to the majority of heroes"
In addition to that, the card also has solid bulk and a strong attack that not only does 160 damage, but also heals 50 damage from each of your Pokmon every time you use it
If you can copy it, it kind of becomes worth the mana investment, except you could just play a card that was worth what you're paying in the first place, and copy that