I have an idea In regards to his needed nerf. I like that he's a 2cc ally with an ability like this. However it's pretty clear how many broken combos will ensue from this ability at this cost. My proposed nerf would be tk change the ability to:
Non-hero abilities activated with shadow energy cost one less shadow energy to activate.

This change would prevent a hero from obtaining large swathes of SE from abusing combos with these guys, while still removing the opportunity cost from using certain abilities (like say, aldmores conduit, or any of the location abilities).
This would prevent the infinistealth of moonstalker, the T2 weapon summoning combo of baddy (though a starting hand of three children still scores you the weapon)
Aramias extreme extreme item summoning prowess (I found some pretty crazy combos with her, the aldmore, and the trading port location) and well, it alleviates all of these seemingly broken combos. But, it still leaves the aldmor with a great T2 summon, or 2cc ally in general.