Drawing cards is vital in Magic, and with Gix in play, whenever a creature you control deals damage to an opponent, you can choose to draw a card and lose a life for each creature
Ashiok, Nightmare Muse While I expect Ashiok to be a nightmare to deal with in Standard, they're a lot less impressive in Commander
When placed in your graveyard, you can return the Zodiac Dragon to your hand instead
the former keeps resources flowing throughout the game, while the second digs deep into your deck for an answer or to set up a win
Still, the ability is expensive enough that having the mana around to actually use it isnt guaranteed, and it isnt like any of these modes is really going to make you feel like youre getting there Mana filter lands usually arent very good in Limited