The upgraded version has too much of a gap compared to the normal version (more than double) and the cost is the same. Either Up the cost or reduce the ammount of turns.
The idea itself is great! For Quint. the monster cannot be targeted AT ALL, by harmful effects or helpful. With this card the creature gains temp. immortality and you are able to buff it. However, the main problem is that how do you decide whether a spell is harmful or helpful. Take mutation for example, you have no idea whether its going to give you something good or a piece of garbage. Or rage potion as another example, the +5 is a buff, but the there's also the -5. I don't think that the game can be programmed with a bias that humans have.
