It's another non-in-universe take on an in-universe mechanic, considering its similarity to spree, the mechanic on cards like Three Steps AheadThree Steps Ahead from Outlaws of Thunder Junction
Just having this in play shaves off 1 mana for each creature you cast
Abilities, two of them: Flying and Regeneration
If a creature with persist that has +1/+1 counters on it receives enough -1/-1 counters to cause it to be destroyed by lethal damage or put into its owner's graveyard for having 0 or less toughness, persist won't trigger and the card won't return to the battlefield
Witherbloom Pestilence Specifications Reasons to buy + Commander provides card draw, lifegain, and +1/+1 counters + Meticulous, grindy playstyle + Blows Witherbloom Witchcraft out of the water Reasons to avoid - Sacrificing smartly is a delicate art Witherbloom Pestilence is a Golgari (black-green) deck that focuses on an aristocratic strategy, sacrificing your critters for greater gain
The section about him from MTG Wiki reads " the Codex Vocifera is a centuries-old tome of convoluted mystical knowledge that has become grouchily self-aware