This page contains content that may or may not be canon to Databrawl.
Corruption "Hearts" were the corrupted equivalent of Program Hearts. They are no longer canon as of December 15 - December 16, 2019.
Unlike Program Hearts, nobody liked to eat them, including Corruptions, because unlike Program Hearts, they were solid as rock from the surface to the core. It is unknown whether or not they would've contained an Essence, as their concept was originally created long before Program Essence was introduced to the canon lore, however they more than likely would've had no Essence within them.
They were nowhere near as healthy as Program Hearts for Corruptions. According to DuncanDunclub,"If [Corruption Hearts] were to be implemented into battle, then it would only provide 10 health at most", which is a dramatic difference from the 60 health that Program Hearts provided in-game before they were revamped to be weaker and give a regeneration boost.
They never appeared anywhere in-game, not even when Corruptions died in the Battle Zone.