I like this card especially for the stunning and the small chance to kill. But cards in this game tend to be simple and usually have no more than 2 functions in one card. This card has 3 functions which I think will be too many for one card. IMO, I would recommend losing the death-triggering effect and lower the cost.
I think the idea with the death effect part is to ensure that you get at least one death effect regardless of whether the instant kill works or not.
I believe the goal was to give a way to power all those death cards that need
effects, but also stay useful in other situations as well.
So the death effect part is just a supplement to the kill chance...
You are right though, it would be cool if it could be condensed a bit to make it more elegant... I'm not sure how to do that though