Abomination Appendix Vol. I: Underground Monsters

From publisher blurb: The Abomination Appendix is a series intended to provide OGL alternatives to classic monsters that cannot normally be used. The ruleset is mostly 2nd edition although it incorporates a single-save system. You may notice some inconsistenciesin terminology between volumes; it took me a while to find the language that I felt most understandable. Abomination Appendix I focuses on underground-dwelling monsters: Burrowers Cave Giants Kongamoto Merrow (5e-inspired) Miasma Serpents Avesa Rakshasas Tunnel Brutes