Shemeska
Adventurer
To mortals, there's no practical difference between an archfiend, slaad lord, protean lord, archangel, etc and a deity. Any of them are capable of reducing you to a pile of ashes in the time it takes to blink if they so chose to do so.
But outside of the mortal perspective, there's one big difference between the various planar lords and a deity. A planar lord is a physical manifestation of their alignment; an archfiend is literally abstract Evil made flesh. Many of them completely predate mortals and gods alike, and they represent a form of that alignment or ideal untouched by mortal belief.
On the other hand, a deity is mortal belief writ large. A god represents a mortal conception of an ideal or an alignment. It's a much more personal and conceivable notion of a universal abstract, rather than the purified, possibly alien version that the archfiends, etc represent.
Metaphysical distinctions aside, the difference between universal abstract and mortal belief tends to place limitations upon both types of creature. Planar lords are largely bound in power to their native plane, while gods face no such restrictions. Of course, an archfiend for instance is going to mangle a god or anyone else that picks a fight inside of their domain, but on another plane, the deity will have the upper hand (though planar politics and radically different goals and scope of goals typically keeps the two from interacting).
I'm much more influenced by the 2e, classical Planescape view of things here, rather than the 'gods are big monsters, archfiends almost as big monsters' that you'll get from for instance, 4e. Totally don't care for that perspective. It cheapens the meaning of such beings to just slap on some extra hit dice and treat them as just a larger monster to fight. They deserve more than rolling initiative against IMO.
But outside of the mortal perspective, there's one big difference between the various planar lords and a deity. A planar lord is a physical manifestation of their alignment; an archfiend is literally abstract Evil made flesh. Many of them completely predate mortals and gods alike, and they represent a form of that alignment or ideal untouched by mortal belief.
On the other hand, a deity is mortal belief writ large. A god represents a mortal conception of an ideal or an alignment. It's a much more personal and conceivable notion of a universal abstract, rather than the purified, possibly alien version that the archfiends, etc represent.
Metaphysical distinctions aside, the difference between universal abstract and mortal belief tends to place limitations upon both types of creature. Planar lords are largely bound in power to their native plane, while gods face no such restrictions. Of course, an archfiend for instance is going to mangle a god or anyone else that picks a fight inside of their domain, but on another plane, the deity will have the upper hand (though planar politics and radically different goals and scope of goals typically keeps the two from interacting).
I'm much more influenced by the 2e, classical Planescape view of things here, rather than the 'gods are big monsters, archfiends almost as big monsters' that you'll get from for instance, 4e. Totally don't care for that perspective. It cheapens the meaning of such beings to just slap on some extra hit dice and treat them as just a larger monster to fight. They deserve more than rolling initiative against IMO.