This could be a nice compliment to the Sundial / Silence type of utility card. It fits the theme of entropy as disorder well... what is more chaotic than a failed coupe de grace? That being said, i have a couple of thoughts regarding this card as a shield vs. being a general permanent:
Seeing as how this is a one shot card, that takes up valuable deck space, it should not be a shield. Ideally, you would not need to ‘keep from being killed’ in the first place. I think that as a utility card, people could find some creative uses for it. Some symbiosis with dissipation shield (or ?) would make it more exciting, not to mention that as an effect card, it would be a counter to momentum and poison.
I think that the original cost is a bit high, considering that 6/7 ttw rush decks are not uncommon , and if your spending all you’ve got maintaining staying alive, what’s the point? Finally, can it be destroyed? That might be necessary for balance sake, if it isn’t a shield… but it would be interesting if your opponent could not even see that it is play at all... until he realizes that you are not dead like you should be!
Nice work!