What exactly counts as an outcome? For example, is each creature attacking a shield an outcome? What about Pandemonium? Is each creature affected an outcome, or is the whole spell just one outcome?
Also, let's say that you have an Ice Shield and you use this ability. If the enemy's creatures are still not frozen by the 50% chance, do they still count for an outcome, or is it only whenever it's favorable?
Tbh I think just having all of these default to 100% on the random part and have the ability nerfed to only two outcomes per each use. That way it's reliable in that it's used to ensure certain effects. After all, having the card say that the next three random outcomes will be favorable is a bit deceiving when it's very possible that the next three random outcomes are disappointing in that they don't end up how you want (again, the example of the Ice Shield).
EDIT: You would also have to make fitting nerfs to the upgraded version as well.