Valley Floodcaller allows you to give Flash to all noncreature spells, allowing you a bit more freedom with when you play Enchantment, Sorcery, and other cards
She also only triggers when you sacrifice creatures rather than whenever they might die which greatly ups the burden on sac outlets
Lots of graveyard decks out there and as a player who gets reeeeeally salty when my graveyard goes away, I can tell you it is absolutely worth it including more grave-hate in your deckbuilding
The modal cards tend to cost more than what youd pay for just one of the effects
Azure Beastbinder A fairly strong card in Bloomburrow Limited, Azure Beastbinder is a great way to keep one of your opponents threats in check
Black-Green Creature (28) Bristling Boar Centaur Courser x2 Colossal Dreadmaw x3 Ghalta, Primal Hunger Gravewaker Grazing Whiptail x2 Greenwood Sentinel Hitchclaw Recluse x2 Jungle Creeper Llanowar Elves x3 Pelakka Wurm Ravenous Chupacabra Reclamation Sage x2 Ursine Champion x2 Vampire Sovereign x2 Verdant Sun's Avatar Vigilant Baloth Walking Corpse Instant (4) Moment of Craving x2 Titanic Growth x2 Sorcery (3) Enchantment (1) Land (24) Forest x10 Foul Orchard x4 Swamp x10 Ironically, this Golgari deck might be the best one for players who want to start playing mono-green decks