Npc vs Mutants Relationships tutorial - Into The Zone mod for S.T.A.L.K.E.R. Shadow of Chernobyl

First, you need to have a unpack gamedata.
Second, you need too know how spawn a npc and create a new faction.

• In game_relation.ltx, add a new "species" (friend_human in my example) for monster_communities with monster_relations like that:

  [monster_communities]
  ;номера team которые присваиваются соответствующим видам
  ;255 - команда не задается
  communities = actor, 255, human, 255, arena_monstr, 39, boar, 40, bloodsucker, 41, flesh, 42, dog, 43, pseudodog, 44, cat, 45, chimera, 46, giant, 47, zombie, 48, burer, 49, controller, 50, poltergeist, 51, snork, 52, fracture, 53, bird, 54, rat, 55, tushkano, 56, friend_human, 57

  [monster_relations]
  ; actor,human,arena_monstr, boar, bloodsucker, friend_human
  ;=============================================
  actor = 1, 1, -2, -2, -2, 0
  human = 0, 1, 0, -2, -2, 0
  arena_monstr= -2, 0, 0, 0, 0, 0
  boar = -2, -2, 0, 1, -2, 1
  bloodsucker= -2, -2, 0, -2, 1, 1
  friend_human = 0,0,0,1,1,1

  So the new "friend_human" species will be friend with bloodsucker and boar.

• Next step, create a new stalker "type" in m_stalker.ltx and use this new monster communities (species = friend_human):

  [stalker_dark]:stalker
  $spawn = "stalkers\stalker_dark" ; option for Level Editor

  ;species of monster
  species = friend_human

• In spawn_section.ltx, use this new stalker type (stalker_dark) from m_stalker.ltx:

  [escape_stalkerdark_respawn_1]:stalker_dark
  $spawn = "escape_stalkerdark_respawn_1"
  character_profile = sim_dark_stalker_general
  spec_rank = regular
  community = dark_stalker

• Finally, create your new faction with all that it need (game_relation.ltx, death_manager.script, death_items_by_communities.ltx , se_respawn.script, xr_statistic.script, string_table_general.xml, character_desc_darkstalker, system.ltx ...)
  And spawn it.

Result, this Dark Stalker member find a new pet!

For this screen, i edited actor vs mutants relations (mutants are friends with actor).

By this way, you could create specifics relationships between specific npcs and mutants species.
As a hermit stalker that mutants doesn't attack, or a strange faction (old Sin Faction) which is neutral with controlers...