On the other hand, though, the resulting Hero Power is powerful, but it (expectedly) lacks support. On one hand, having unspent Mana implies that your deck is slow, but on the other hand, it’s not something so uncommon when running a slower deck, which Druid has tools for. The real interesting thing about this Quest is that it requires little action from the player to complete.
It is probably not overpowered – far from it, one could say – which, for many players, I know, will automatically make it “garbage”, but I don’t think it is.