What does Shadowform do to other classes' Hero powers?
Solution 1:
The name and icon remain the same. A warrior for example, loses his Armor Up! and gains Mind Spike just as a priest would. The same applies (if I recall correctly) to an aditional Shadowform. You gain the Mind Shatter ability with the corresponding icon. Just as it says on the card.
Edit: This shows an example of a Warlock gaining Mind Spike by using Lorewalker Cho.