As simple and cut down as plugins come these days. Because sometimes you don't need all the extra bells and whistles. This plugin lets you customize death messages, and that's it. Nothing superfluous. No compatibility issues. Just a featherweight utility to bring a bit of levity to your untimely demise.
Just drop the plugin .jar file into your plugins directory and boot the server (or load via other means if you wish). If a messages.yml is not already present in plugins/CauseOfDeath, the default will be loaded and saved.
Editing the messages.yml file is simple. You can use Minecraft's color/formatting codes with the ampersand character (&). The text macro %victim% refers to the dying player's name. In the case of a monster- or player-induced death, %killer% refers to the killing entity (either the player's name or the type of monster). If killed by a player, %weapon% refers to the name of the weapon/item used by the killer (or its type if it's unnamed). If killed by a projectile by either player or monster, %projectile% refers to the type of projectile responsible.
If you feel like changing things up on the fly, use the command /cod-reload to reload all the stored messages from the messages.yml file.
That's really it. Enjoy!