I love me a good namedrop! Yep, I've done terrible, terrible things in the cursed oasis, tiz true! There's one particular thing about why the Codex is so bloody good on this map, in fact that's how I "discovered" both the codex, the fact that it rules cursed oasis, and that the oasis is really, really easy if you prep right. And that there were more brutal, if not as simple minded, strats out there than just prepping Mystera on a Goblin Sorcerer. I was on a GobSocMystSpam VT clearing world tour, and that dungeon was giving me a hard time. So I was looking for ways to che... err, test the mechanics for power level, as it were, to find something to snag that badge while midlessly spamming fireballs as I have been everywhere else. And the thought occured that I didn't in fact know what happens when you heavy fireball a guy who allready has retaliate fireball. So I tried it on the dragon in cursed oasis. Turns out it works in your favor. Say, looks like an entry for the undocumented feature list!
This also works in Dragon Isles I suppose, so the codex makes fireballing bossess that were not ment to be fireballed quite easy (provided you can replenish both health and mana, ofc).