It’s not. You have to add it yourself because many right thinking people think this sort of thing is stupid. 
Honestly, the concept of critical successes and critical failures is a pretty decent one. But there’s no table that will ever cover the various circumstances properly and most of them are filled with stuff that is just downright stupid. (See above).
Generally, critical hits and misses are best done with some mild, fixed mechanic (“You do max damage” or “you lose your next action”) and let the GM or the players fill in some interesting description for why.
On the other hand, some people like the random chance of hitting themselves in the crotch with their own halberd, so they make up tables like that.
Also, there’s really no reasaon to roll when you’re shooting someone in a gun-to-the-temple execution. That’s silly. YMMV though.
Re Critical Misses
For a while, I played a Beastman (see your Complete Book Of Humanoids) who was gifted with Monstrous Dexterity (I think it was a 21) and had a blowgun and poisoned darts. He could kill most enemies from long range before the rest of the party engaged them. This aggravated the DM, but he couldn’t do anything about it without pissing me off badly. Then, I rolled a 1. “You stumble and fall upon your blowgun, shattering it.” He had what he wanted, and I couldn’t object because it was right there in the rule book. The other characters were upset (they were in more danger now) but the other players were pleased because now they could get some xp.
Back To The OP
It helps a great deal if the DM knows the players. Will they want a hack and slash? A lot of puzzles? How good are they at roleplaying?
Railroading, shoving the players down an adventure with no choices, is despised. But randomly deciding to do something completely outside the box is also frowned upon (Unless you’re playing an insane character). You can’t just teleport to the UnderDark. How do the characters know about the UnderDark? How do they have the power to teleport that far? etc. If the players show interest in the UnderDark, the DM can work it into the game gradually setting them on a journey down below and reminding them that their characters know nothing of the place.
Man, your GM sucked! A good GM would have said, “You inhale when you meant to exhale. Roll save versus poisons.”
I agree that a pre-made module is probably the way to go for the first couple of sessions. Just take the time to read the thing at least three times, and try to imagine running through it yourself as a player. What are some things you might try as a player that the module doesn’t cover?
Read over your player’s character sheets before the game starts and try to think of creative ways to use the abilities listed, because you can be sure the players themselves are planning moves before the game even starts (Expereinced players will have their cheese thought out before they even roll up their character).
I’d also encourage you to use your common sense…no matter what the rules say. Let the players try silly things, but apply the appropriate modifiers. (My personal example: When the fighter and the bard were fishing for giant crabs in the town lake and the fighter managed to fumble his sword over the side of the boat. He jumped in after the sword. I asked him one time if he was sure he wanted to do that, then when he said yes, I let him…then reminded him that chainmail is not really ideal swimming attire. Things went badly for the fighter…)
My first group had an in-joke that went (always in a really hairy situation) “I throw a potion!”
In the first dungeon we fought a particularly nasty golem, my mage was low on XP so our fighter (in full plate, wielding a longsword and a tower shield) said he’d throw me a health potion.
The DM: “You throw… a potion… while a giant golem is towering above you, poised to strike and you’re holding a weapon and shield you find it prudent to search your pack and THROW a potion?”
Him “Uh… well, I have HP and he needs it”
You drop your shield and weapon to rifle through your bag (to be charitable he even allowed both that and the throwing in one round)…
Attack of Opportunity!
You throw the potion…
Attack of Opportunity!
(Next round)
I pick up my weapon and shield…
Attack of Opportunity!
Did I mention we bottlenecked the golem since all our other characters were ranged in some way? There was literally no way for this golem to hurt me anymore (he used some one-off AoE) AND the fighter had nowhere to take a 5-foot step to in order to drink a potion safely.
We got out of it at least…
I give you the Gazebo of Doom: Eric and the Gazebo: An RPG tale. - Brunching UBB
And the Amulets of Pretty Much Instant Death: http://www.bookofratings.com/dnd.html
Not to nitpick, but this is an egregious abuse of the attack of opportunity rules.
He was totally asking for it!
(Also in that post I clearly meant HP, not XP, on the off chance anyone was confused)
I’ve been a DM for almost 20 years now, and although I started out with published modules, they were never what I needed from them. The main reason was that they were all published in English, and my groups first language is Dutch. I could never use the environmental descriptions, and found that I was winging it most of the time anyway. After a few tries I decided to do away with published adventures altogether.
This helped me in several ways to become a good DM (yes, I’m convinced that I’m a good one). First, it lets you tailor your aventures to your group. This will let you focus on what your group likes and avoid the things they dislike. It also lets you run a smoother story. Adventures will better follow each other and it will let you build a living world.
Currently, I hardly prepare sessions anymore. I’m intimately familiar with the world my players live in and can come up with an interesting story at the drop of a hat. I actively encourage them to come up with new and interesting ways to do things. We play on the Outer Planes (PlaneScape campaign settings) and weird things are the norm, so if my players want to chase that serving wench and follow her home, I let them. They may even find out that she is a high ranking member of an Anarchist cell, or a scout for draftees in the Blood War. The players want to break in to her house? Sure, let them. I’ll just draw up the floor plan of my sister’s appartment. I need a family dynamic? Either she’s living alone (not unusual if she’s a free agent), or she has the same dynamic as one of my colleagues. I need a neighbor? I have several aunts that can function as one. Borrowing from real-life with a twist is the best way to bring authenticity to any session.
The greatest challenge? Continuity. If you mention that the wench’s neighbor is a 6 foot, 230 lbs. woman with hairy armpits and a burlap dress, you have to make sure that the next time they meet her, she is at least still 6 foot and 230 lbs. Dress and personal hygiene may vary, but more likely will not. You have to make sure that she’s recognizable. Binders with copious amounts of notes may help, but a lot of head work is necessary too.
My tips for new DMs: don’t bother with published adventures. You may screw up with your own adventures the first times around, but you will become a better DM because of that. Don’t worry if you screw up. Be honest to your players and tell them that you made a mistake and want to make a change. Or just live with your mistake and continue with it. It doesn’t really matter (unless it royally screws over your plot).
If you find that your players are not enjoying your adventure (it will happen sooner or later, every DM has been there), don’t be afraid to let it drop and start something new. Don’t be too attached to your own adventures. What is enjoyable to you might not work for someone else. Don’t force your players into anything they don’t want.
In the same vein, if you consistently don’t like what your players are doing, find out why it is they are doing that and try to come up with an adventure that incorporates their wishes as well as yours.
This is the only advise I can really give: make sure you have fun with what you are doing. Usually, if you, as a DM, has fun, the players will follow. If you can enthusiastically present your adventure, your players will become enthusiastic about it too. But if not, don’t be afraid to change directions.
The advice I give to starting DMs is this.
before you get into it, decide if you really like the source materials, and story telling in that setting. IF you do, then take some time before you start. I always loved rolling up characters(particularly evil bastard NPCs), and desiging dungeons and adventures. I got a portfolio of charcters and adventures ready to use at a moments notice. The first rule of DMing is any people fun to play with will never do what you expect them to. And they will get pissed with a railroad campaign.
The Elven princess screaming in the market square for help to save her father from the tribe of orcs out in the forest= Always ignored. Something you don’t even remember saying, that you must have ad-libbed for ambience, about an oink from the town well= PC obesssion. So when they climb down the well you just pull something out of the notebook that will work as a sewer adventure, and go with it. Just remember to call all the kobalds in your story pig-men, and pull out a necromancer-experimenter to replace the Kobald King and they will never know the difference.
There are really only three adventure types; City/town, Sewer/dungeon, wilderness. Have a ready supply of at least 4 of each, for the campaign level and adapt as appropriate. And for maps just steal something from a different publisher, and rename the buildings and towns where required. If you don’t enjoy coming up with stories, then maybe DMing isn’t for you.
#2 Whenever you start a campaign, run each person through a solo, or at most two person adventure to get them to the group up point. It avoids the"You all happen to be in a tavern" cheese, and when alone, even people who are shy will have a chance to make their own character decisions without being pulled along by the crowd. Each PC actually develops a personality(and maybe a secret or two ;)) before teaming. It really makes it so much more fun for everybody when the group gets rolling. PCs who are just stats become accounting. PCs who have a personality and only use stats to represent them to the world is when things get good.
Ahhh A Doppleganger attacks the party, but I crit and destroy it.
The table that Lute linked to looks pretty good. It adds some random flavor without being too disruptive.
Or, of course, just have a grateful farmer offer them a reward of a sack of potatoes for rescuing his prize pig that fell down there last market day.
The best RPG description I’ve read can be found in the Shadowrun core rule book. It says the DM and players are not in competition with each other, and are not really playing a game as much as creating all the elements of a story. It’s more like acting than board gaming. That’s what you’re missing in the computerized versions of D&D. There’s a human element to it, and the rules are not the point of the game. Players and GMs happily toss the rules out the window when they conflict with an interesting plot device.
I know a lot of that seems off topic, but I think approaching the original question of “how does this stuff work when the system seems so fragile?” from the viewpoint of the GM and players being in cooperation rather than competition is an important part of answering it.
Back in the day (70’s early 80’s) I DM’d ALOT. Everyone told me I was damned good at it.
As other posters have noted, players know you can’t have made up EVERYTHING. So they will play along. However, players like to have freedom and so you try to strike a balance. In addition, you may have players that try to push the limits.
The way I handled all this was to:
- The world is a dangerous place. This is one mistake I see many DM’s making…their world isn’t scary enough. If you played in my world you had BETTER be on your toes. This means scouting to get the lay of the land (Thief players LOVED playing in my worlds). You barge into things and you WILL die. If you all of a sudden want to teleport blindly into the Everdark…well I might let you (the other option is for the session to stop for a few days while I flesh it out)…however you most likely will run into something fast that will kill you.
Related…let the players be able to fail and for that failure to have consequences so that they REALLy don’t want to fail 
Make the world scary. Keep people on their toes. This also helps prevent infighting and group split ups as they have other priorities.
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Make the party partly driven by exterior events. Many DM’s make the ‘mistake’ of creating a ‘sandbox’ world where players can go anywhere. This can work but it is easier and IMO more exciting to have them somewhat driven by events. I was told many times that people liked playing in my worlds because other creatures/people really seemed to have their own agenda. You could, for example…have the campaign start with an invasion from Hell (which happened very similar to the game Oblivion but I did it first 20 years earlier
). One of the longest running campaigns I had started with a ‘routine’ 1st level mission which ended them lost and stranded underground…which lead further and further down… -
Have ‘stand alone’ adventures…that you can pull out and use.
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Have premade random encounters (think of them as mini-adventures) ready. One word of note…DO NOT let players know they are stand alone/plug in…because it loses some of its ‘magic’.
It works…and is, IMO, MUCH more fun than playing D&D on the computer games. I’d still recommend it to this day.
Oh, absolutely. There are very few computer games that manage to get a good sense of story (Mask of the Betrayer is the best I’ve seen), and that’s the main reason I’d love to get back into pen and paper gaming. It’s also the most daunting part of it - stat-balancing I have practice with, story-telling… not so much.
The most daunting thing about pen and paper RPGs for me is how much time they consume. That’s a hurdle just too high to leap with a two year old kid and a wife who expects not to be the only source of income.
Honestly, if I had the time and friends for it, I would play D&D all the time. You don’t have to worry about telling a GOOD story! In fact the quality of the stories in D&D campaigns is usually not high. What you get in return for a mediocre or even bad story is a higher level of immersion than you can get in almost any other medium. That’s not Jason Bourne shooting a terrorist or Legolas leading an impossible defense, it’s YOU chopping down an orc or hacking a government computer terminal. There’s no other experience like it. I think even people who don’t like RPGs would admit that much.
God, yes. I’ll readily admit that lately (as in the last few years with respect to the a span of a decade, decade and a half) I’ve gone from roleplayer to rollplayer. I still love all the elements of RP: setting, characters, plots, everything. However, these days I can’t really be arsed to control my character and come up with personal storylines that I’m motivated to push myself. I’m much happier creating a character and a personality and letting that personality react to the plot as it unfolds. It’s less immersive than it could be, but it’s how I manage to have fun. If, after I go through and craft a character I like, the DM turns to me and goes, “Okay, what do you want to do?” my brain shuts down and I lose a great deal of my interest in the game. (This happened in the last P&P game I participated in. It was online, and I lasted only a few sessions before I gave up.) If, however, you tell me that as I arrive in town, a group of bandits is hurrying out of a store waving crossbows, you bet your ass I’ll jump right in there. I just need a direction to point my character in.