Need a good excuse for Hextor to be starting wars among LE groups...

[Gavinfoxx]

As a backdrop for my campaign, I want to have various Lawful Evil (and some Lawful Neutral) organizations having wars against each other. Get Aboleths vs Beholders, maybe. Maybe Devils vs Ethergants. Maybe an evil human empire vs Yuan-Ti. Whatever. I want the threat of the places and people the party cares about being used as slaves in some war they have no part of to be one of the overarching themes of the campaign, perhaps. Or perhaps the good gods being overwhelmed by the fallout of so many places flaring into large scale conflict at once.

The problem is, I'm not quite sure of a reason for Hextor (the most obvious entity to be doing this) to do this; a lot of these things are, if not his followers necessarily, aligned with his viewpoints. Any suggestions?

[Palanan]

If Hextor is the god of war, conflict and destruction, then I'd think that's all the reason he needs. I wouldn't expect there's any a priori reason why one LE group has to be nice to any other LE group, and spreading destruction can certainly be accomplished by pitting one evil empire against another.

Beyond this, it's certainly possible for different sects of Hextor's faith to each have their own agendas, some of which conflict naturally with each other, and some of which may be devoted to manipulating wars in Hextor's name.

[el minster]

Read the lawful evil handbook

[Bohandas]

to ensure the flow of lawful evil souls. War keeps the groups in a state of xenophobia, regimented militancy, blind obedience, and jingoistic chauvinism, as well as increasing the population's rate of turnover due to the bloodshed

[Kelb_Panthera]

Because they're not all kneeling to a theocracy that rules in his name is -plenty- of reason. That is, straight-up imperialism.

[el minster]

Because they're not all kneeling to a theocracy that rules in his name is -plenty- of reason. That is, straight-up imperialism.

Not just imperialism also colonialism or any part of MAIN

[Bohandas]

Another possibility, if you want to get a bit meta, is that he wants to level their warriors up. And really it's only a tiny bit meta, because I've seen theories that the [redacted] wars in [redacted] were actually waged to make sure all of the [redacted] empire's soldiers had combat experience in case a real war broke out, and that procuring sacrifices may have only been a secondary goal.

EDIT:
And now that I think of it, procuring or choosing sacrifices could ve a goal here too

[TiaC]

He is the god of tyranny, absolute rule. Tyranny is all about expanding and consolidating power, both as a means and an end. The ideal tyrant believes that everything should be unified under the tyrant's sole rule. As long as there exists more power to be had, the tyrant will seek it. LE rulers can be made to see this, which will drive them into conflict, both to subjugate each other and to fight the greatest threats to their existing power.

[Asmotherion]

Well, I like the "I compete for souls with Asmodeus and other LE deities" as a motive.

Or like, the whole continent is under LE rule, but each section has it's own Ruler who follows his own LE Deity, and it's a war to see whose authority will be absolute.

[Berenger]

The problem is, I'm not quite sure of a reason for Hextor (the most obvious entity to be doing this) to do this; a lot of these things are, if not his followers necessarily, aligned with his viewpoints. Any suggestions?

Whether the contestants know this or not, these wars are actually a tournament (to the death). Hextor wants to choose a worthy mortal as his divine champion and right hand. You win by leading your troops to victory in a bloody unholy crusade to exterminate or enslave the rival factions (and everything that happens to stand in the way).