From publisher blurb:
This is pure gonzo-light, science-fantasy, eldritch pulp awesomeness! O5R compatible (including Crimson Dragon Slayer) scenario pretty much requiring The Islands of Purple-Haunted Putrescence (if you don't already own it, get it - you'll thank me).
Within Battle For The Purple Islands, you'll come across cultists, cannibals, talking apes, and other strangeness... and finally the chance to meet H.P. Lovecraft! Random tables up the wazoo - that will add to any jungle exploration and hexcrawl / sandbox setting. Also, fantastic artwork and superb layout by Glynn Seal of MonkeyBlood Design.
Kort'thalis Publishing will handle all your purple needs from now on.