I've started doing speed runs now that I've played through the game upward of fifty times and have mastered training the creatures, and I always just use a very old trick to do this land, with my own twist.
You get your town built (for the fireball miracle), then take the "please don't trow me" guy, which has its own ring of influence, slow down time, and carry him in the largest segments outside of that little ring of influence that you dare to Lethys's temple. (Note that this is an evil solution, but the quickest and easiest, and you will hardly get your hands dirty.) Sacrafice him at Lethys's temple; He'll get stuck in the altar without dying or giving Lethys power, and the AI doesn't know to move him.
Now, you get some rocks (I use the ones from around the waterfall) and set them against the side of Lethys's temple, and set them on fire. It will rain occasionally, so diligence is key. Eventually, the Egyptian town will be destroyed, and the pillar will drop. DO NOT STOP, as Lethys will rebuild the village if there are any people left in it, which will make the pillar rise again. I usually go ahead and destroy Lethys for good measure, just to get him out of my way.
Now, take those flaming rocks and influence-hop as before, but toting the rocks, to not the first but the middle village, the Indian one. Use the rocks to kill everybody, not sparing a soul, though you can take prisoners if you have room in your village. (Hovering a flaming rock over people will set them on fire, as well as nearby buildings and trees/fences/farms. You need to keep track of your little immortal helper, as he will try to run home. Bookmark him and pull him back into town when he's almost gone. ) After there are NO citizens left, you have two options:
a) Wait a few minutes, and the victory will register, and another pillar will drop, or
b) Place one of your (adult) villagers in the town as a missionary, and wait about ten seconds. However, you have to keep them alive until you take the last village, or you will lose the pillar. I usually only do this on the last (normally first) village, as this village will usually tick over as you're taking the last.
Now, the Japanese village presents an option. If you've been taking some care of your town by this point, you can convert it by normal methods using your influence, or just do the same as the previous village. For speed, torch it, but for resources, convert (not that resources last long in Land 4). Since you did them out of order, and the last village, normally the one that triggers wolves/fires, is the one that frees your creature now, you don't have to deal with Lethys's evil miracles, and you also can just wait out the last bit and not battle his creature. (This only works if the last village is the first you take care of; If you go 2-1-3, instead of 3-2-1, then you will have to deal with fire and wolves at the same time. You can also do 2-3-1, but it is more difficult and tedious. As long as village 1 is last, you're good to go without harassment.)
Lethys will open the vortex and give you the creed, then go on about how you killed him (if you did). If you destroyed his temple as well as his towns, you now get to see some really dramatic and touchy camera shots of an empty plateau. If you want to throw supplies through (if you're speed running, you don't), then put immortal guy near the vortex (Not too close! The one thing that will kill him is the vortex.) and drop a town center scaffolding for permanent influence by the vortex. (Set scaffolding isn't sucked in.)
That is, in my experience, the only way to get through the entire land a) without severe frustration, and b) in one session, so you don't have deal with ludicrous save times (turning off autosave goes without saying).
Sweet! I had figured it was already out there somewhere on the internet, anyway; After all, though I've seen no documentation of the working backwards glitch, everything else in it is fairly well-known.
Yeah, I finished this challenge for the first time once pretty soon after posting my walkthrough. It took me about fifty tries to get the timing right. Looks kind of neat when you finish, though.