Rule One: Don't procreate. Having offspring merely poops out someone who you will expend a great deal of resources on and who'll end up trying to kill you, ruining all your hard work if they happen to be successful. When you're dead do you really think you're going to give a fuck who's running your Empire?
Therefore if you feel the overwhelming need to nurture something, get a puppy.
Rule Two: Always leave yourself a variety of escape routes. You want a party of adventurers to eventually overrun your base, it's good PR. If your Loathsome Lair kills every last would be Hero that enters it, sooner or later they'll stop trying. That being said, you can't let the worthless cunts kill you in the process or what's the point?
Rule Three: Stagger your Citadel's level of deadliness in accordance with the readily available talent of the local hero pool. No sense hiring a Green Dragon to star in your Labyrinth if you can only expect to attract Adventurers in the 5-8th level range. Just get a Salamander or a couple of wyverns, save the payroll until your PR campaign starts bringing in some bigger hitters.
Rule Four: Always leave a survivor. What's the point of being deadly as fuck if no one knows about it? This applies on the battlefield as well as in your home labyrinth. Survivors make the best ad men and you don't even have to pay them. They're so eager to tell their tale of surviving your deathtrap that no advertising agency of yours could ever hope to equal that sort of publicity, especially not for free.*1
Sometimes these survivors are so good at telling the gruesome tales of their experience in my Fell Catacombs, that I'll pay various actors to follow them around and buy them drinks in taverns so they'll tell their stories over and over.
Which leads neatly into...
Rule Five: Always be prepared for bigger fights on short notice. Normally, when a party of big name Adventurers is assembling for a Major Campaign, you'll hear about it through your intelligence apparatus unless you're a complete yambag. And quite frankly if a high level group of Heroes takes you unawares and unprepared, you fucking deserve to lose and I personally hope you die in the process.
Less competition for me in the Hero-Luring business.
Therefore if you open a Labyrinth rated for 1-6th level clients, you have to be ready for that rogue, asshole group of 9-14th dungeon crashers that will try to blow through your establishment looking for easy loot. If a surprise party like this manages to blitz through your whole setup and makes it look easy, you're going to look like a fucking pansy and that's going to cost you in credibility, not to mention the assets they slaughtered in the process.
You can't have that.
Therefore you keep some aces up your sleeve just in case some arrogant higher level dicks try to get all shitheel on you.
I myself have an Undead Dragon*1 stashed away in my Labyrinth's basement as well as an Iron Colossus*2 cleverly disguised as a big, normal statue that I can deploy against intruders who are more powerful than they should be.
These aces usually pay for themselves in kobolds alone when some smart ass, lazy band of reasonably potent hacks come rolling through my property, expecting easy money and experience.
Dark Lord levels one through twenty:
Lvl 1) Scary Kid
Lvl 2) Obvious Future Criminal
Lvl 3) Dirt Thief
Lvl 4) River Bully
Lvl 5) River Boss
Lvl 6) Town Gang Member
Lvl 7) Town Gang Hero
Lvl 8) Town Gang Leader
Lvl 9) City Gangster
Lvl 10) City Councilman
Lvl 11) Politician
Lvl 12) Dark Mayor
Lvl 13) Conservative Senator
Lvl 14) El Presidente En Darko
Lvl 15) Conqueror
Lvl 16) Emperor
Lvl 17) Evil Fucking Cunt
Lvl 18) Dark Lord
Lvl 19) Dark One Percenter
Lvl 20) No-Shit, Legitimate-Ass High Dark Lord
And there you have it, dear readers. Follow the above five rules and with a lot of luck and/or a whole bunch of money, you can be a successful Dark Lord. Unless I kill you first, sensing a future rival.
Yours in the spirit of friendly competition,
-Lord Hurderoth
May His Troof Be A Word To Your Matriarch
*1 Under 20th level? Then you don't want to fight a fucking Undead Dragon. Trust me, boyo.
*2 This cost me an insane amount of money. Obviously the only ones capable of making an automaton of this size and complexity are the Dwarves, and since they know they're the only ones capable of making it, they charge accordingly. To put this in perspective for all you modern readers (because I stand astride both Space and Time), an Iron Colossus is the Bugatti Veyron of labyrinth-defense auto-motile technology.
