Food and Fellowship, a white/black/green deck that has two commanders as its face cards: the currently unrevealed Frodo, Adventurous Hobbit, and Sam, Loyal Attendant
If a deck manages to do that effectively, that will probably be the best Giants build.
Interestingly, Dark Houndoom still takes advantage of Darkness Energy by allowing it to discard Darkness Energy (then a Special Energy type card that both increased attack damage and passively damaged the Pokmon it was attached to) in order to power up its Dark Fire attack
This means that it can be used as one of two Commanders in a deck, provided that the other also has a Partner keyword
During your turn, you can play a Basic Pokemon onto your Bench , play a single Energy card onto the Energy spot, evolve a Pokemon, and play Trainer cards