try this one

# Group inheritance
#
# Any inherited groups prefixed with a g: are global groups
# and are inherited from the GlobalGroups.yml.
#
# Groups without the g: prefix are groups local to this world
# and are defined in the this groups.yml file.
#
# Local group inheritances define your promotion tree when using 'manpromote/mandemote'

groups:
  starter:
    default: true
    permissions:
    - essentials.spawn
    - essentials.kit
    - essentials.kits.starter
    - essentials.sethome
    - essentials.tpa
    - essentials.home
    - essentials.tpaccept
    - essentials.tpdeny
    - plotme.limit.2
    - plotme.use
    - plotme.use.add
    - plotme.use.remove
    - essentials.build.*
    - -grief.prevention.ignoreclaims
  Owner:
    info:
      prefix: '&f[&5Owner&f]'
      suffix: '&d'
    default: false
    permissions:
    - '*'
  Dev:
    info:
      prefix: '&4[&6Dev&4]'
      suffix: '&d'
    default: false
    permissions:
    - '*'
    - -bukkit.command.op.give
  Admin:
    info:
      prefix: '&9[&3Admin&9]'
      suffix: '&d'
    default: false
    permissions:
    - '*'
    - -bukkit.command.op.give
    inheritance:
    - Mod
  ChatMod:
    info:
      prefix: '&e[&0Chat&fMod&e]'
      suffix: '&d'
    default: false
    permissions:
    - plotme.limit.*
    - plotme.use
    - plotme.use.add
    - plotme.use.remove
    - essentials.build.*
    - -bukkit.command.op.give
    - -grief.prevention.ignoreclaims
  Grass:
    permissions:
    - essentials.kits.grass
    - plotme.limit.4
    - essentials.afk
    - essentials.suicide
    - iDisguise.cow
    - -grief.prevention.ignoreclaims
    inheritance:
    - starter
  Stone:
    permissions:
    - plotme.limit.6
    - iDisguise.chicken
    - iDisguise.sheep
    - iDisguise.pig
    - essentials.fly
    inheritance:
    - Grass
  Iron:
    permissions:
    - essentials.kits.iron
    - iDisguise.mushroom_cow
    - iDisguise.wolf
    - iDisguise.horse
    - iDisguise.donkey
    - iDisguise.ocelot
    - iDisguise.iron_golem
    - iDisguise.squid
    - iDisguise.mule
    - -grief.prevention.ignoreclaims
    inheritance:
    - Stone
  Gold:
    permissions:
    - iDisguise.slime
    - iDisguise.skeleton
    - iDisguise.zombie
    - iDisguise.witch
    - iDisguise.snowman
    - iDisguise.villager
    - iDisguise.spider
    - iDisguise.undead_horse
    - iDisguise.skeleton_horse
    - -grief.prevention.ignoreclaims
    inheritance:
    - Iron
  Obsidian:
    permissions:
    - iDisguise.pig_zombie
    - iDisguise.baby
    - iDisguise.wither_skeleton
    - iDisguise.creeper
    - iDisguise.zombie_villager
    - -grief.prevention.ignoreclaims
    inheritance:
    - Gold
  Diamond:
    permissions:
    - iDisguise.magma_cube
    - iDisguise.silverfish
    - iDisguise.bats
    - iDisguise.cave_spider
    - iDisguise.charged_creeper
    - iDisguise.enderman
    - -grief.prevention.ignoreclaims
    inheritance:
    - Obsidian
  Sir:
    permissions:
    - iDisguise.ender_dragon
    - iDisguise.ghast
    - iDisguise.blaze
    - iDisguise.bat
    - iDisguise.wither
    - iDisguise.giant
    - iDisguise.ghost
    - -grief.prevention.ignoreclaims
    inheritance:
    - Diamond
  Mod: []