Okay, I went and downloaded DGDobrev's save and I was able to defeat both the Shelter Elven (easier) and Human (harder) stacks using the double Evil Book @level 2 strategy.
I did defeat the 3 easy Spider / Snake stacks in the Catacombs such that when I defeated the Shelter Dwarven stack I was level 5. I put a point into Order to get me up to 36 Mana and was able to cast my first Level 2 Evil Book and then by splitting the Werewolf stacks it was able to work on the Werewolf and Sprite and then on round 5 as it was close to death I cast my second Level 2 Evil Book. The first one had taken the 8 Elves down to 4 and then only lasted another turn or two, but by that time, the damage had been done and the Sprites and Fauns were gone. My Vamps then helped take down the Werewolves with the second Evil Book as it had gotten the Elves down to 1. Starting placement of your Vamps made a difference between 1 dying and not.
As far as the Human stack, they were much tougher, but once again I split the Guardsmen and Swordsmen (moving towards the latter since they did less damage). I did have a fortuitous Lightning Bolt take out 14 Bowmen, 9 Priests, and 3 Inquisitors when my first Evil Book was about 50% health. This allowed my Vamps to switch to Bat mode and slap the second Evil Book right next to the group of shooters. After that I managed to take out the rest of the shooters and then my second Evil Book was able to take the Swordsmen and Guardsmen down to about 50% when it finally died. As I mentioned above, once the melee troops are the only ones left in the Human stack it is just a matter of time before your Vamps can slowly take them down and finish it. I actually probably could have done better as I forgot to cast Poison Skull when I had gotten 7 Mana and had let my Evil Book absorb 76 damage from an Eviln, which I was trying to get the Swordsmen to hit, but at this point it did not matter since there were only melee troops left.
Compared to Ball of Lightning I'll say that it was a bit easier, but all these strategies (except for maybe the Phoenix which is very easy @level 2) are fairly dependent on finding the right sequence of events.
By the way, I did a little experiment and Runes given during levelups are dependent on the area. I used the "levelup" cheat when I was in Portland to level 5 and I had enough for Meditation Level 2, Concentration Level 1, and Chaos Level 2 when I was level 5; however, since I made level 4 in Dragandor and Level 5 in the Shelter the Runes given were then different and I couldn't get Meditation Level 2 so that's when I went with Order Level 1. Note that I could have also gotten Diversion if I wanted instead of Order Level 1, but I never tried that strategy to see if it was better or not.
If you can get Meditation to Level 2 when Daert is Level 5, then all these strategies are a lot easier when you start with 40 Mana instead of 36. To have a chance, though, you should probably take out the 3 easier Spider / Snake stacks in the Catacombs to give yourself a chance of reaching level 5 after defeating the Dwarven stack.
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