1. Count it yourself in a database. 2. Use the StatsCore API, which requires StatsCore to be installed on that server.
If there is StatsCore, you can use: PHP: $server = $plugin->getServer();$statsCore = $server->getPluginManager()->getPlugin("StatsCore");$log = $statsCore->getLog();$kills = $log->getKills($name);
make it on my own on death event get last cause - if instanceof EntityDamageByEntityEvent if damager instanceof Player and u are in.
Ok. But maybe you can check if StatsCore exists and use maybe, because StatsCore was designed to save servers' database size by providing statistics to other plugins.
Still haven't finished the database. I asked @iJoshuaHD to finish it for me but he seems to have forgotten.