…Is there a trick to keeping these fellas fed? It seems like they consume a lot more Energy than I could ever earn back, even on the hardest difficulty setting.
Best way is probably to play 5 Shadow Lords Multiplayer matches each day to get the daily rewards from it. You’ll get 1200 Astral Energy for doing so, along with a 600 Energy bonus for winning at least 1 match. Even though SL MP does allow the use of Guardians and Items, it might be good to forgo using them (the expensive ones anyway) for the purpose of building up Astral Energy.
Another way is if you have a large amount of KI Gold or Astral Gems, you could transmute a Guardian to gain Gems and Energy, then buy the same one to get it back plus an Energy bonus.
Although if you know you can win a certain fight rather easily it might be good to use a lower rank guardian for its lower maintenance cost.
I’d recommand having a friend to do these challenges.
I usually pick RAAM with a Dram of Focus to get the damage going, beat my friend 4 times and let him win the 5th Match.