Kill rewards
Pay the killer shards, with a separate switch for the action bar and the chat line.
Kills.Enabled starts as false. Nothing is paid until you set it to true and run /afk admin reload. The victim keeps their shards. A player who kills themselves is not paid. An amount below 1 is skipped.
Kills.Worlds is a list of world names. An empty list pays in every world.
Players
Kills.Players.Enabled allows player kills. Amount is the default. Permissions works like AFK rewards: the first permission the killer has wins. The sample is afkplus.kill.hunter for 10 shards. Put the largest tier first, because operators have every permission.
Players.Actionbar.Enabled shows Minecraft.KillActionBar. Players.Chat.Enabled shows Minecraft.KillChat. Turn either one off without turning off the payout. Both lines accept {amount}, {currency}, and {victim}.
Mobs
Kills.Mobs.Enabled starts as false, so a zombie grinder pays nothing until you opt in. Mobs.List maps a Bukkit entity type to a shard amount:
List:
ZOMBIE: 1
SKELETON: 2An unknown type is skipped with a console warning. Mob kills use their own Actionbar.Enabled and Chat.Enabled. The sample hides the chat line and keeps the action bar. {victim} is the mob's custom name, or a readable type such as Zombie.
Suggestions
Turn on Kills.Enabled and leave Mobs.Enabled false until you have listed the mobs you actually want to pay. Set Players.Actionbar.Enabled to false if the AFK action bar and the kill line fight for the same space. Grant afkplus.kill.hunter from the Permissions page only for the tier you put first.