Demons and Devils?

[Ryan Kappler]

What is the most common ways that demons and devils travel from the Abyss and Hell to the Material Plane?

Once defeated in combat, do they automatically teleport back to their own realm?

[Jack Rift]

Summons or Gates on how. Exception for Demons in Golorion being Wound world. If summoned once defeated, yes they are banished. I some of the other cases, no they are dead. The Abyss or Hell usually will respawn said fiend in a few centuries.

[wraithstrike]

They dont normally have plane shift so they are normally brought here by a caster. If they are defeated and they were called they actually die. If they were just summoned they go back home.

[Lincoln Hills]

Some of the most powerful ones have the necessary SLAs to arrive under their own power, and bring along a few buddies.

The denizens of Hell would probably regard this as a "business trip," packing along a few minions to send off on detached duty and arranging a later pick-up time and place for them to go home.

In the case of the Abyss, on the other hand, low-ranking demons who have won the approval of a higher-up might be 'rewarded' with a field trip to the Prime Plane to kill and destroy at random. In that case, of course, getting back home is entirely up to the individual.