I am designing a rpg. The concept is earth is populated with monsters, undead, demons, and other supernatural beasts and horrors that mortals can't see. Some humans can see this though. Player races include Dhampir, Fallen Angel, Dwarf, Elf, Hobgoblin, Human, Orc, Hellblood (half-fiend), and Shifter (near lycanthropes). It is set in our world at our time, yet it is full of fantasy and mystery. I have been drawing inspiration from multiple rpgs, movies, tv shows, video games, religion, folklore, and fantasy.
I want to work in different religions, folklores, and fantasies.
I have been working on a bestiary, but it is lacking.
Does anyone have any ideas for monsters, beasts, and horrors that you would be willing to let me use?
Get a copy of George Eberhart's Mysterious Creatures. It's about 800 pages of real world monsters from cryptozoology and folklore.
And then Katherine Briggs, An Encyclopedia of Fairies.
Yeah, the library is your best resource here. There are thousands of books that have been published with categorical or encyclopedic listings of monsters from various world religions. Any local library is bound to have a few. Plenty of online sources as well, starting with Wikipedia.
I recommend starting with a theme, or you're looking at years of research just to scratch the surface.
Instead of inventing a game from whole cloth, you could consider Open Gaming systems and borrowing from them...
D&D 3.x has PILES of neat Monster books. PILES OF THEM. Drivethru has hundreds of OGL monsters from single two page workups to thick creature catalogs.
IF you make your system using the OGL and IF you attribute your sources in Section 15, you can use these works as the basis for your own.
What kind of system are you creating? Is it more about your setting? Are you familiar with the OGL and how it works?
For example, there are several open games now outside the d20 ruleset, like Mongoose Legend, Open Quest, Action! System and West End Games released all D6 games under the OGL as well...
In theory, that would be a good source, but in practice, most 3rd party monster books have made everything but just the stats product identity, which means you really can't re-use them, since if you can't use the name or description, well, all you have is stats.
With that said, Paizo has 4 monster books and put them up on their reference document
http://paizo.com/pathfinderRPG/prd/monsters/monsterIndex.html
Maybe check out Borges' The Book of Imaginary Beings?
Also have a look at the awesome Monster Brains blog for images drawn from fine art, pop culture and pulp that could spark some ideas: http://monsterbrains.blogspot.co.uk/ (http://http://monsterbrains.blogspot.co.uk/)
I'll second Borges.
Henderson's Book of Barely Imagined Beings concerns real creatures, which are pretty amazing and strange.
Some good suggestions here!
Some good inspirational novels would be the Dresden Files, by Jim Butcher.
Urban Fantasy, about a modern Wizard in our world where things you've mentioned exist in the background of society.
Also the Iron Druid, by Kevin Hearne, about a Druid originally from the Celtic period living in the modern world.
Similar theme as Dresden Files, with a more Celtic feel to it.
http://mentalfloss.com/article/12646/11-legendary-monsters-asia
Some cool Asian monsters
Or just pick one/several of the following:
https://www.youtube.com/watch?v=S1SV0LInE-s
(yeah, not even close to worksafe)
I normally plough through Wikipedia - lots of examples of fantastic and mythological creatures at just the right level for a RPG Bestiary.
Quote from: soltakss;792827I normally plough through Wikipedia - lots of examples of fantastic and mythological creatures at just the right level for a RPG Bestiary.
Wikipedia can be a decent source if you know where to look on it.