Here's the draft of Chapter 5 from my Dangerous Dungeons sourcebook for OSRIC. Warning: It's big - there are more than 300 pages of Open Source monsters - both conversions of older AD&D monsters and a number expressly written for this project
Of the converted monsters, you’ll find unique takes on old favorites like the Slaad (Slaasthak), Beholders (Ocular Despots), Githyanki (Annunakim) and Mind Flayers (Cephaloids), several new varieties of dragons, undead, dopplegangers, giants, demons, devils, daemons, and angels.
There are also a number of new monsters adapted from folklore and fantasy literature around the world, including several creatures from H.P. Lovecraft’s Cthulhu Mythos and Lewis Carrol’s Jabberwocky. Amongst the new monsters are also several new varieties of fey and other humanoids that take a more traditional, folkloric approach to these mysterious creatures.
At the end of the draft are comprehensive tables for Randomly Determining Monsters by Type.
Take a look, let me know what you think and feel free to use these monsters in your own OSRIC products. Enjoy!
*Update (9/14/18) Some flyleaf illustrations have been added. The wonky layout issues were fixed, and an index has been added to the pdf.