You can get a raw copy of this card for around $230
Auctioneers reserves the right to refuse admission to the premises, and/or to refuse participation in any auction at any time at Bruneau & Co
They link to a GitHub repository, but unfortunately there seems to be no existing implementation to try it out yourself quickly
When it comes to Proliferating, Atraxa, Praetors Voice is the obvious pick for Commander
Though it does come with other downsides (it doesn't negate the effect of the magic cards it destroys), it's still a solid situational choice that allows the player to destroy high-value, continuous effect cards that may otherwise jeopardize the entire game
This does not mean graveyard synergies are bad, but Lorehold is not Witherbloom