Diluvian Primordial A very expensive creature with no cost reduction, no tribal support, no flash or anything to keep it flexible, and it allows you to cast one spell from each opponent's graveyard
One particularly damning thing to note is this chart: This table shows that with 7 Swamp and 7 Plains, you will have the required Plains to cast a turn-3 Territorial Hammerskull only 85.9% of the time (on the play, in absence of mulligans or card selection)
Hes seemingly in vogue right now, but in the long term I see Bruvac as a relatively safe card to have in the format
Arcane Signet, Smothering Tithe, Dockside Extortionist, Thassas Oracle and others have become ultra-staples displacing entire classes of card from the format, and community sentiment around new legendary creature designs which play too well with the mechanics and needs of Commander is similarly mixed
A card that has been in a certain flavor of green and black decks for quite some time, Hermit Druid provides one of the cheapest and easiest ways to fill your graveyard
We are thrilled to hear tale of a new Ring-bearer in possession of the serialized 1:1 The One Ring