This release is part of the source code release as outlined in this announcement.
This add-on is designed for DeathMessagesPrime, and adds kill and suicide messages for ender crystals under natural.EnderCrystalKill and natural.EnderCrystalSuicide, respectively.
The config allows you to configure which player is considered the "killer"; the player who placed the end crystal (default) or the player that hit it, causing it to explode.
Since version 1.2, tracking bed kills/deaths by player has also been supported.