How often do you use the monsters or adversaries from your system of choice? How many do you create on you're own from scratch? What's the percentage? I know for me no matter what system im using the bad guys provided just rarely seem to fit the setting without major changes and fairly frequently won't fit at all. I'd say I use provided adversaries maybe 10 or 20% of the time, the rest are designed from scratch.

I quit using published monsters years and years ago. Too many players have read the books and all the mystery is gone. It's easy to tweak an orc or dragon to make it different from the routine and keep things interesting. Elves don't have to be ripped out of Tolkien. The best monsters are often other people.

Very much system and game dependent. Rarely do I hew to the games descriptive and personality descriptors, but the mechanics it is probably half-and-half.

I usually use the monsters as statted. Sometimes as written too. Unless the writing somehow contradicts whats been established in other books for the game. And sometimes you just have no choice but to ignore an entries background and come up with something yourself.

Example: I used the creatures and aliens from star Frontiers pretty much exactly as is. Occasionally tinkering a unique creature using the rules given for that. But not tweaking the established creatures unless its something of Sathar design as they are known for creating variants. And on uncharted worlds Ive had to work out stuff as I go. Often just renaming an existing creature.

In D&D, especially BX I tend to leave the creatures stats as is. Personality tends to be on a case by case basis as in BX about nothing is flat out evil for the entire species. So you might run into friendly red dragons, not so friendly gnomes, or whatever. changing weapon and armour loadouts for those that use them is useful for making the leaders and guards for example stand out and its part of the rules even.

Whereas in Tunnels & Trolls or Gurps you pretty much have to create monsters yourself. They give a few examples. But really you are expected to DIY alot of stuff.

I was going to say I mostly use as-is, but I guess I mostly use NPCs and mostly make my own stat blocks for them. For monsters I either use as-is or tweak, eg for 5e I changed fire beetles to make them tougher, more like a BX fire beetle. I tend to use OSR adventures in 5e so often need new stats. Running Valley of the Red Apes on Wednesday I took the 3hd 19 hp 5e Ape, then to make a Red Ape raised it to 5 hd 32 hp and STR 18, d8+4 damage and Rend if both paws hit for another 2d8+4. The 2 high level barbarian PCs hacked through a bunch of them no bother.

One definite advantage is instilling some uncertainty about the world in the hearts of your players. When playing a single system for a long time and utilizing the provided critters it can ruin the sense of adventure. When they encounter a big green lizard thing in a cave and have no idea of its actual capabilities but have to rely on their character's knowledge or beast lore rolls or whatever it takes on a very different feel. Making all your own stuff takes time and effort but I think its worth it in the end.

When running monsters from the book I tend to run them by the book. This works well with my current group of players who haven't read the book. I don't need to put the time and energy into designing lots of new and unique monsters.

Back in the day every one of us had practically memorized all the books, so new and unique monsters were definitely a thing. There was a popular suggestion in GM advice at the time to describe the monster rather than naming it, but even that only work for so long. Besides how many ways can you describe a giant floating ball with a big mouthful of teeth and a bunch of little eyes on stalks?

Making new monsters is one of my favourite parts of playing Gamma World and the like. Makes the players have to think when they have no idea at all what the monster can do.

The great thing about home rolled monsters is that it stops the arguments of "but, the Book says..." dead in their tracks. Yes, orcs don't use Ice magic, but these are not orcs...

Monsters, rarely.  Animals, much more often.  That being said, my setting has a number of non-standard beasts, which of course I had to stat out.

Quote from: DavetheLost;1010622When running monsters from the book I tend to run them by the book. This works well with my current group of players who haven't read the book. I don't need to put the time and energy into designing lots of new and unique monsters.

Back in the day every one of us had practically memorized all the books, so new and unique monsters were definitely a thing. There was a popular suggestion in GM advice at the time to describe the monster rather than naming it, but even that only work for so long. Besides how many ways can you describe a giant floating ball with a big mouthful of teeth and a bunch of little eyes on stalks?

Making new monsters is one of my favourite parts of playing Gamma World and the like. Makes the players have to think when they have no idea at all what the monster can do.

The great thing about home rolled monsters is that it stops the arguments of "but, the Book says..." dead in their tracks. Yes, orcs don't use Ice magic, but these are not orcs...

You are absolutely correct but Ill be a little cautious in agreeing with you as it may seem as though its an indirect reference to another thread I started recently. This thread has NOTHING to do with that other one, although now in retrospect I can see a correlation.

I was not intending reference to the other thread.

I agree with you that the book provided monsters often don't fit a GM invented setting. With the same applying to PC races. Cue arguments about "the Book says I can play a half-dragon half-demon Lesbian Stripper Ninja..."

It does draw some odd looks however, especially among young, new players. At a recent game in which I'm playing I mentioned that in my upcoming campaign mixed races dont exist. (no half anythings) Nor are there Demon people, Angel people or Dragon people. A couple of my fellow players balked stating that if your going to play D&D, you need to play D&D. One of the other more veteran players came to my defense and together we explained to these guys (fresh out of high school) the concept of setting and how the rules are simply a medium with which to experience it.

You could also show them the many official editions of D&D in which there are at least no Demon People, Angel People, or Dragon People. As for half-races, it was laways DM's prerogative what to leave in and what to leave out.

As long as there is consistency within the setting, custom monsters are part and parcel of GMing, IMO.

In my last three games, I've started using custom stat blocks--even when the monster is standard.  That is, I put the monster in a document in a format that I find useful, and do this for all of them even when I don't change it.   It accomplishes three things:  

A. Makes it easier for me to mix and match different monsters in the same encounter.
B. I'm more likely to change it if needed, since I've already done most of the work of entering the base stat block.  
C. Since I never open the monster books at the table, the players have no clues whatsoever what I'm using, except as the way I describe them.  

It's not that much work, since I tend to limit a given campaign to a relatively small set of creatures.  I only started doing this for reason A, but found the other two things were a nice side effect.  Well, that and also that I do not like the standard stat blocks in the games I am running.   Reason B is all in my head, and I'm sure other GMs would find better ways to accomplish the same thing, but it works for me.

I am down for using either one. The standard monsters save you time, and you can just tweak them here and there to fit.