At the moment, I lost interest in Minecraft, so I stop development, here is the source code: https://github.com/truekenny/MyLineagePvpSystem

Versions
Way

Group of players
External differences
Description
* Its configurable.
In the beginning, all composed in the «Peaceful players».
When you hit another Peaceful player or player mode «PVP» - you also go for 30 seconds in the «PVP».
If you kill a player of the «Peace Group», you become a «Killer». Being in the «Peace Group» and attacking «Killer» - you do not go in mode «PVP».
For each kill «Peaceful players» - you karma falls by 10 points.
In order to go back to the «Peace Group» - you have to kill sheep, cows, zombies or skeletons.
For every mob - your karma is made up by 1 point.
If you die as a «killer», that karma is made up by 10 points.
Differences between groups
Commands

Enabling rpg mode caused an uproar on my server. Be careful.
Disabled by default, you must change the setting rpg.enable.

Each creature has level.
The farther away from spawn in the world, so it is more. Each 100 meters = +1 level for mobs.
In the Normal world level begins with 1, in Nether with 25, with 50 in The End.
Damage in «RPG»
Entity with Y level has entity with X level: damage = default_damage * ( (Y / X) ^ rpg.difficulty ).
It is spread on the players.
Experience in «RPG»
Experience falls from mobs killed by you, only if the difference in level is not more than 5 (Hello, Lineage).
local: statusPeace: You went into a peaceful mode statusPVP: You went into a PVP mode statusPK: You have become a murderer, are imposed on you the effect of slowing, fatigue, weakness statisticPK: PK statisticPVP: PVP statisticKarma: Karma statisticDeaths: Deaths statisticDeathsMore: (from the other players) statisticModePeace: You are in a peace mode statisticModePVP: You are in a PVP mode statisticModePK: You are player killer drop: inventory: peace: 0 <-- 'between 0 and 100, 0 - 0% drop chance, 100 - 100% drop chance.' pvp: 10 <-- 'between 0 and 100' pk: 100 <-- 'between 0 and 100' armor: peace: 0 <-- 'between 0 and 100' pvp: 9 <-- 'between 0 and 100' pk: 99 <-- 'between 0 and 100' experience: keep: peace: true pvp: false pk: false karma: kill: peace: -10 <-- 'must lower than 0, if kill peace player' self: 10 <-- 'must more than 0, if die' mob: 1 <-- 'must more than 0, if kill mob' world: doesNotWork: creative,world_creative doNotCleanKarma: creative,world_creative time: purple: 30 <-- 'must more than 5' rpg: enable: true <-- 'DEFAULT FALSE, MUST TRUE FOR ADDON «RPG»' difficulty: 0.33 <-- '0 - original game balance, 0.33 - easy, 0.5 - medium, 1 - hard, 2 - HELL, 3 - Impossible game balance (damage = default_damage * (LVLDamager / LVLVictim) ^ difficulty)' expDifficulty: 0.35 <-- '0 - original game expDrop, 0.33 - more, 0.5 - low (dropExp = default_dropExp * (LVLDamager / LVLVictim) ^ expDifficulty) + 1' metersPerLevel: 100 beginLevel: default: 1 nether: 25 theEnd: 50 levelAlwaysVisible: false skipVillager: true <-- 'if TRUE then do not change name for villager' levelDifferenceForExperience: 55 <-- 'At what level difference with mobs will drop experience' protectMobsOfFireDamage: false <-- 'Protect mobs from burning?' stillProtectMobsLVLOfFireDamage: 50 <-- 'if protectMobsOfFireDamage == false then mobs over stillProtectMobsLVLOfFireDamage levels to defend in any case' name: CREEPER: Creeper SKELETON: Skeleton SPIDER: Spider GIANT: Giaht ZOMBIE: Zombie SLIME: Slime GHAST: Ghast PIG_ZOMBIE: Pig Zombie ENDERMAN: Enderman CAVE_SPIDER: Cave Spider SILVERFISH: Silver Fish BLAZE: Blaze MAGMA_CUBE: Magma Cube ENDER_DRAGON: ENDER DRAGON WITHER: Wither BAT: Bat WITCH: Witch PIG: Pig SHEEP: Sheep COW: Cow CHICKEN: Chicken SQUID: Squid WOLF: Wolf MUSHROOM_COW: Mushroom Cow SNOWMAN: Snowman OCELOT: Ocelot IRON_GOLEM: Golem HORSE: Horse VILLAGER: Villager default: Level