Argh, almost had it, but Earthmother screwed me.
After studying the map layout, I basically concluded that victory and defeat hinges on one thing: can you kill that 3rd level golem. The glyph layout is extraordinarily generous (BURNDAYRAZ, HALPMEH, AND GETINDARE all near the entrance), and once you've killed that golem you have a whole bunch of easy popcorn to build up food and make it through those stretches of empty space to explore the map. My game plan was to immediately head along the north exit and kill the 2nd level troll. With a 1st level kill along with it, that takes you to level 2, strong enough to beat that Golem if nothing goes wrong. The availability of Soul Orb (don't get greedy! You need mana burn immunity more than that keg) means the murkshades and wraiths cease to be problematic.
Unfortunately I bounced to Earthmother when I leveled up to level 2 and couldn't kill the plants to reach the Golem without incurring game-ending corrosion. This is definitely possible, but it comes down to sheer dumb luck. If I'd had Dracul as my 2nd level deity I'd have been fine (would have needed to convert a potion for piety, but not a big issue). I wonder if you prep both Binlor and Mystera if Earthmother gets replaced...