Stupid DM mistakes

[Frog Dragon]

So what mistakes have you made behind the screen that just make you facepalm afterwards? I have two

I looked up the sorcerer spells from the wrong spot on the table and didn't realize it until earlier. The player had been playing with a level higher casting

The party fought a ghoul rogue who fell a bit too quick. Reason? I FORGOT THAT THE UNDEAD HAVE CRIT AND SNEAK ATTACK IMMUNITY. Seriously. And the ghoul one was recently and I'm supposed to be able to handle this system pretty well

[t_catt11]

Meh, missing something in the rules, allowing an extra crit, whatever. Those happen all the time.

The only really stupid ones are the ones you refuse to admit, or do anything about.

[Rhiannon87]

I keep track of initiative via index cards. I also use index cards to tally monster hit points. It is depressing how often I will look at a card, intending to read off a character's name, and then announce how many hit points the monster has left instead. :: sigh ::

[Choco]

I feel you about forgetting undead are immune to crits... My campaign is rather light on the undead, so the players got through their first and only undead dungeon dealing crits to the various undead, and only at the boss did one of em go "hey wait a minute..." Yeah, I was wondering why they were getting through that dungeon so easily!

Any time I have to use a Deus Ex Machina or fudge enemy dice rolls to give the players a chance I view that as a failure, even in the situations where one or more of the players roll 1's over 50% of the time in the session (it has happened twice so far).

Allowing a Chaotic Stupid character to exist for more than 3 acts of utter stupidity, hoping they would get better.

Creating a sandbox game for players who actually WANT to play through a storyline, video game style.

[Piedmon_Sama]

I once described a round stone tower as "ninety feet tall" and "thirty feet wide" before realizing this made it a three-story tall dome and not the tower I was imagining. V_V

More recently I let my players crit a plant-creature, thinking it would make the encounter easier but still take them a few rounds. They took out a 136 HP gargantuan centipede topiary guardian (they only go up to huge in the book) in one round.

[Telonius]

Not me, but a previous DM...

Allowed Order of the Bow Initiate's ranged precision to apply to all attacks gained by Manyshot.

... and didn't fix it through 20 levels of adventuring.

[valadil]

I let a newish player I didn't know very well be the bad guy spying on the party. It didn't ruin the campaign, but it did make me hide under the table for a few sessions.

[Boci]

Not me, but a previous DM...

Allowed Order of the Bow Initiate's ranged precision to apply to all attacks gained by Manyshot.

... and didn't fix it through 20 levels of adventuring.

In moderate-high powered campeigns that wouldn't be a problem. Maybe the DM saw it recomended and didn't realize the assumed power level of his game was below average.

On a similar thread one poster claimed to have had a DM who thought the amount of attacks you get on a full attack is based off your dex modifier.

[Hyooz]

Started my first campaign at level 1.

[graymachine]

I assumed that a party of 6 12th level PCs could handle 2 greater wraiths (equal CR). Ended in a TPK.

[Glass Mouse]

Let's see...

* Didn't give any treasure after a two-session dungeon crawl (granted, in a low-treasure campaign, but still...)

* Ragged on a player OoC for IC jerkiness (oops...)

* Dropped a waaay too heavy hint of something that was supposed to be subtle. Now they know too much.

* Forgot that Explosive Runes deal damage to more than one person.

* Gave plot crucial items to the "is never there and doesn't even try when he is" guy.

* [Deleted for the sake of my self-esteem]

I don't think you'll have trouble finding possible mistakes to make

[Tyndmyr]

I let them use diplomancy.

[Akisa]

I didn't let them use diplomacy.

[Xzeno]

I forgot about a golem's immunity to magic. Sort of worked out though, because the players told me they would be playing rouges and fighters and rangers and stuff, so my dungeon was built for non-magical classes. They instead played a sorrcoror, wizard, druid, barbarian and ranger. Of course, the golems' DR worked on arrows and they mad short work of the animal companions with a lucky crit.

[TheCountAlucard]

My party's sailed through rather a lot of encounters; one factor for why is that the Warlock in the party laughs at most creatures' pitiful touch AC and proceeds to go, "pew pew pew." As a result, I made a note to myself specifically to use some Demodands in a fight, since they have Spell Resistance (and it also made sense in the plot).

Then, during the fight, I forgot about the Farastu's Spell Resistance, and the fight ended pretty quickly.

[Tyrmatt]

Totally misgauged the power of some guns I let the party pick as starting weapons and simultaeneously forgot to give the badguys bullet resistant armour.. You should not be forced to look up a table to determine the size of the pile of shredded meat left of the guard on the gate, 20 minutes into the first session.

[Talanic]

See, if I had forgotten that undead were immune to crits and realized it later in the same dungeon - and if those undead were sentient - I'd have it be that they were feigning true death after taking hits that would have killed living people. I'd start rolling bluff rolls for future 'defeated' undead.

Me? I fall into the "Okay, so what's his name?"

"....."

Waaaay too often.

I make other mistakes too, of course, but that's what came to mind first.

[DragoonWraith]

What do you mean by the "OK what's his name?"?

[Sir_Elderberry]

4e, the party is fighting a ghost Solo who's pretty badass, and the barbarian walks up and hits for like 60. I'm like "crap, I was going to have fun with this fight, too". That's when one of the PCs (poor, foolish PCs) saved the mistake my drawing attention to the word "insubstantial". They still lived, but they had to work for it.

[Katana_Geldar]

What do you mean by the "OK what's his name?"?

Forgetting the names of various NPCs as well as PCs, I don't make that mistake as a GM, but often do as a player.

[Starbuck_II]

I forgot about LA:
A girl played a Pxie.
The guy played a greatsword wielding Sorceror.

Yes, he used true strike to offset -4 non-proficiency.

The pixie was way stronger due to the invisibility, flying , etc.

[stenver]

Allowing a first time player play a druid.

Seriously, it takes more then an hour and a half to set up and explain his character and he STILL wont fully understand what he is capable of. For example, instead of turning into animal and charging with his animal companion, he shoots with a bow(non metallic, 1d8-2 damage) and forgets all about his animal companion

Letting a first time players play tier 1 classes(not because, they wanted power, but they all CHOSE them.. we didnt even have time to play)

[Katana_Geldar]

^ This is why I don't let new players play Jedi, despite the arguments. You don't need another layer of learning on top of learning to play.

[Volos]

I allowed a player to stack the improved critical range from the improved critical feat (PHB), a keen weapon, and a certian class feature. Not to mention I let him play with his 'lucky' dice. I test rolled them afterwards, his d20 never rolled lower then 15. It also had a huge bubble in the middle.

Microwaved dice are fun.

So I started making sunder monkey monsters who would destroy every rapier he attempted to wield untill he got one made of adamantite.

[Piedmon_Sama]

Allowing a first time player play a druid.

Seriously, it takes more then an hour and a half to set up and explain his character and he STILL wont fully understand what he is capable of. For example, instead of turning into animal and charging with his animal companion, he shoots with a bow(non metallic, 1d8-2 damage) and forgets all about his animal companion

Oh yeah, I've done this too. Two times, I've let two different first-time players start with a Druid and both times they were frustrated because they didn't know what they could do and neither did we. :/

If I ever have another player who's new to 3.x I'm just going to say "I recommend not doing a Druid, it's an advanced class and frankly none of us are very familiar with it."

OTOH, I've found clerics are an extremely forgiving class and good for first-timers. Probably because it's so tough to kill the bastards.

[Berserk Monk]

Started my first campaign at level 1.

And?

[Inhuman Bot]

And?

1st level is boring, I suppose.

[evil-frosty]

I would think high mortality rate might also be an issue, and i dont find first level boring it can be interesting depending on the campaign style.

[Katana_Geldar]

1st level is boring, I suppose.

A lot of people start there, though.

[DragoonWraith]

I'd say the problem with starting at 1st level is that PCs are ridiculously fragile. It may be very difficult for a newbie DM to avoid an accidental TPK. Starting at 3rd or even 2nd alleviates that a lot.