The wastelands that comprise the Twisted Earth are home to a myriad of horrendously-mutated beings, from intelligent character-types worthy of interaction to simply the cannibalistic or predatory creatures that prey on the weak or solitary. Dangers other than the ever-present radiation and the chemically contaminated ecosystem do exist out there, and are rightly feared by all folk of sound mind. Terrors of The Twisted Earth is a d20 mutant creature sourcebook to be used for Darwin's World or any d20 setting.