My Answers to your questions
1. Are there any other non-TPK DM's out there?
I suppose thre are other non TPK DM's out there. However, I am not one of them (I have had at least one TPK). How do you define a TPK DM anyway?
Is it a DM who ends up rolling ungodly well and lets the dice fall as they may?
Is it a DM who sets up very difficult fights where a TPK is a very possible outcome (could happen with average rolling)?
Is it a DM who has 1st level characters face wizards who cast Circle of Death?
I am of the ilk that sets up very difficult fights.
2. If you are a TPK DM, what's the deal? Why? How does it work?
The deal is this. In most of the campaigns I run, the player tend to spend a great deal of time outside of dungeon situations. This means that they typically have ample opportunity for rest between fights. Fights where the the CR is "DMG appropriate" to the party (Encounter level 5 vs 4 5th level charcters) will always be won by a party if they can rest in between.
Such fights work when the players are in a dungeon, or when they happen in rapid succession. Outside of statistically anomolous dice rolling (refer to jdavis post above), the first few fights are easy. But having 3 or 4 "DMG Appropriate" fights is time consuming. Combat tends to take up the greatest amount of time of all possible activities in a D&D game. 5 fights with Orcs in one day is hard to explain outside of a dungeon.
If your always having fights that the PC's will win, then why have any fights at all? Such things simply end up either impeding the story, or being anti-climatic. I want my fights to be worthwhile events within the game. I also dont want to spend 90% of my game running fights where the outcome is a foregone conclusion.
So instead, I create an in game reason for the enemies to be adequately prepared for the players. If an Orc tribe loses a patrol of 5 warriors, they wont send 5 more to investigate in my games. Here is an example.
In my games, Orcs use watchers who stay back and watch the fight. When it becomes obvious that the Orcs are losing, they flee. This keeps the fight quick. Even if the players kill all the orcs, the watcher can usually escape easily, especially if he was a few hundred feet away, and stayed hidden. The watcher and any who escape report back to the tribe. The next fight (often a day later) report back to the tribe. The tribe will then get together a larger force of orcs, throw in a few champions (orcs with character levels), and / or bring along a couple of Ogres. They will then set an ambush for the players. For me, this means that the Orcs will have prepared cover and concealment, and there will be a few traps around.
Now, when the players get into this fight, it is still winable, but they have to be careful. If the party flees after a few rounds, I will usually let them, especially if they put a dent into the enemy force. If they stand, and fight, and lose, then they suffer for it. Loss of gold, equipment in some situations. Other times they may be taken prisoner. It depends on the situation.
Either way, the party gets a challenging and entertaining fight, and I only need to run two fights in one session instead of 5 to do it.
I should also point out that I never run a campaign with some 'pre-ordained' prophecy storyline where the players are 'chosen ones'. In those campaigns, a TPK tends to severly break the storyline. In my campaigns, the villian drives the story, but if he kills the party, then new heroes are perfectly welcome to take up the challenge.
The one TPK I remember most happened when my players got a bit stupid (way back in 2nd edition). They took out a humanoid patrol belonging to a very vicious Orog warlord named Rourc. The players tied a survivor to a tree, and gave him a message for his master. They challenged the warlord to an 'honorable' 4 vs 1 combat. Of course, the warlord was not the honorable sort. The players had their 4vs1 with the warlord in the middle of the army camp. They had their arses handed to them by an ILLUSION of the warlord (dropped two players from full hp to zero in one round each!). Then when they finally got past the illusion, the real warlord, got out of his tent, Laughed at the players, called them idiots, then had his army help him kill them. Most of the party was later raised.
If a group of players is stupid enough to awaken a sleeping dragon, then its time to practice extreeme darwinisim. There are some fights I will let the party flee from. Fights against "Final Villians" and fights created by PC idiocy are no holds barred.
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