This article describes each of the Human and Creature groups' loyalties and towards which other groups are they hostile or allied. In general all of the groups are hostile towards Garrett, but a thief must know how to make his enemies fight one another and who will fight who.
- Chaos Beast – won't attack another creation of the Maw, but will attack anything else. The only exceptions are the Pagans who are allied with the Chaos Beasts.
- Elemental – elementals will attack any non-elemental entity. The only exception goes for magically summoned elementals which won't fight their creator, or his allies. In one mission Fire Elementals are seen allied with Chaos Beasts, and in another mission, they are allied with Chaos Beast cousins.
- Hammerite – won't engage other humans except thieves and criminals (Garrett included). They will engage anything non human on sight. The Hammers have an exceptional hate towards Pagans and Undead. Were hostile to the Mechanists, but full scale conflict never came to fruition due to the weakness of the Hammerite order after the death of the Trickster. In Thief: Deadly Shadows Hammerite Guards help the City Watch fighting enemies.
- Human Guards and City Folk – they are generally peaceful towards other humans and will attack anything not human on sight. The basic rule is that most guards will attack Garrett if he enters a restricted area or threatens them and most innocents will run away on the first sight of danger (see the Human Category for more info). In certain circumstances one human guard group will attack another, but those are mostly triggered and pre-programmed. In Thief: Deadly Shadows it becomes more complicated as City Watch will engage criminals or other characters under certain conditions.
- Pagans – won't generally engage humans, except on certain conditions and when on their own territory. The only exceptions make the Hammerites who are enemies with the Pagans. All creatures allied or summoned by Pagans including Chaos Beasts won't attack the Pagans themselves, but will attack any other human or creature not a part of the Pagan culture.
- Undead – will attack any non-undead or otherwise alive entity. Although they don't interact or usually even seem to notice each other, they have the known tendency to amass and help one another more than the other groups.
- Wild Beasts – will attack anything not from their own packs or types. In certain missions Wild Beasts can become allied with Chaos Beasts.