60% stock monsters (hell, I bought all those MMs for a reason!)
30% stock with a twist
10% brand spanking new weirdo beasties
+/- 10% based on the complexity of the game system
+/- 10% based on my mood

When I run games based on known IP or published setting, I am more likely to use stock monsters.

When I run games based on my own homebrew, I am more likely to use modified or fresh beasties.

Quote from: Headless;922290in the last session I ran the players ended up fighting unsubstantial snakelike streamers of fairy fire.

Awesome story! That's inspirational improv!

Quote from: Headless;922290How often do your players encounter situations or creatures not in any books?  

Its a complicated answer because I'm really into mythology and folklore. Like really, really into it, have been since I was old enough to own my own library card. So when I introduce a monster/creature in one of my games, its generally going to be heavily based on real worth beliefs in that monster, to the exclusion of anything a game text says.

I actually think the D&D Monster Manuals were the worste affront to imagination and verisimilitude that Gygax could have unleashed upon the hobby. I hate the "Star Trek Alien" approach to monster design that D&D has largely championed over the years, with all the colour, uniqueness, and bizarre oddity of folklore bled out of mythical creatures to make a taxonomy of insipid encounters.

But, there's big exceptions to this. There are unique monsters or interpretations of monsters in D&D and other RPGs that are wonderful enough in their own right I love to use them in my games. Planescape has some wonderful stuff. Beholders are just awesome. Demogorgons? Yes, please.

Warhammer Fantasy was far and away the best at this though. Skaven, Fimir, Zoats, Dragon Ogres, Slann...all just great, and stuff I'd gladly use wholecloth in my games any chance I could.

It really depends on whether the monster should be known to the characters or not. In a fantasy setting I wouldn't be surprised at some one-off unique creatures--though someone might be able to discover their nature & abilities through advance research. And even common creatures could be different from the RAW bestiary if you want the players, who are otherwise familiar with the rules, to have the experience of being strangers in a strange land--whether commoners getting their first taste of adventure, or even experienced adventurers visiting unknown regions (like Sinbad or Odysseus). But once a "typical" creature's characteristics are established, I think it's better to keep them that way as part of building the lore of the campaign and making the world seem real rather than arbitrary. In short, orcs should be orcs.

In my current LotFP game, all the monsters are unique. I wanted a weird feel for the 17th Century Europe. Moreover, I wanted to capture that feeling of surprise, wonder, and dread for my players that I first felt when I first played D&D years and years ago. To my mind, this meant letting go of orcs and anything rote, and setting before the players things they had never seen before.

I was inspired on this matter by Raggi's LotFP Referee Book, which I think is a terrific piece of work.

Here is the passage that really struck my imagination:

QuoteOne staple in fantasy and horror fiction and gaming is the monster. From the fire breathing dragon to the werewolf to the fairies to fierce man-eating apes, unnatural creatures are an important part of the proceedings. However, fantasy gaming tends to overuse monsters, turning adventures into a safari.

Less is more. A monster should be the centerpiece of an adventure, a sign that things aren’t right. Their presence should be consistent with the setting and the situation, not outside concerns like, “There needs to be a fight here, that would be exciting.” When making out-of-game decisions, implement nothing without justifying the results in-game.

Always be conservative. One monster played up as a central focus to an adventure will be more memorable than any of the twenty monsters in a forty-room dungeon would be. Once a monster makes an appearance, it won’t be so interesting, and definitely not as threatening, as it was the first time. Stretch the use of monsters out over time...

You will note that unlike almost every roleplaying game ever, there is no “stock” list of monsters included with this game. Because monsters should be unnatural and hopefully a little terrifying, using stock examples goes against the purpose of using monsters to begin with. Again, this is from an in game perspective. That the players need challenges and fights is understood, but the temptation is always too great to skim through a standard monster list to lazily fill out an adventure. Don’t do this. Not ever!

I'm not saying people should play this way, or that it serves every campaign need. But for the design aesthetic of Raggi's Lamentation of the Flame Princess product line, it works gangbusters. I've been having a great time building out the campaign this way.

To me this is one example of fulfilling the potential laid out at the end of Volume III of OD&D, when Referees are encourage to take the rules set go off and make something new and unexpected.

So, yes, for another setting, I might be using the stock beasts and races. But for this campaign, I never hit the Players with anything they've seen before. I want them eager and terrified to find out what they'll find the next time they turn a corridor in a ruined crypt.

90%+ of monsters I use are stock critters from the book.  Even unique ones are typically just adding one or two special abilities to a stock monster.  I have made very few homebrew monsters whole cloth over the years.

I cannot recall ever making up a monster's abilities in the middle of a combat encounter.  I have certainly been on the player's side of the screen when the GM did such a thing.  Every time I have realised the GM was doing so, it has felt pretty cheap, like the GM was being somewhat arbitrary.

Quote from: RPGPundit;922767I generally use stock monsters (maybe 95+% just from the AD&D Monster Manual, in fact), but I often alter them in some way.  That's much more common for me than actually just inventing a monster out of the blue.

Heh. Lately I find myself agreeing with the Pundit more than I used to.

This is also how I do it. Take something familiar the players have probably seen, and give it a new twist.

Quote from: Xavier Onassiss;935725Heh. Lately I find myself agreeing with the Pundit more than I used to.

It means you're improving.

About 90% of the monsters I use are humans, but they might or might not have unique PC-like abilities;).

Quote from: RPGPundit;936800It means you're improving.

Well, one of us is!

On a more serious note, what's your preferred method for altering monsters? Do you keep the stat block but describe them differently so the players don't recognize them? Change their abilities? Add new ones? Add class levels to monsters capable of taking them? All of the above?

Quote from: Xavier Onassiss;936912Well, one of us is!

On a more serious note, what's your preferred method for altering monsters? Do you keep the stat block but describe them differently so the players don't recognize them? Change their abilities? Add new ones? Add class levels to monsters capable of taking them? All of the above?

I've used all of those methods.  Sometimes it's as simple as re-skinning them, particularly for humanoids.  Otherwise, it might be to give them some kind of special ability and a slightly different appearance, to suggest a variant of the baseline race.