[Jinix]

I had the same trouble with the spider - the more rounds I went the more bloody spiders dropped down - I was so frustrated I went to Youtube and watched someone sail thru it with 4 trolls.
However, my game did not spawn trolls before the spider-boss fight so I had to keep on trying til it worked. Anticipating the spider's moves helps to align your troops just before he moves. I eventually won it as a soothsayer with Vikings and griffins.
Every time a new game starts the program changes the locations of some spells and items and troops.
With the Princess game I got resurrection spell almost immediately, on the second time thru I never found one until almost near the end of the game.

With WotN I'm level 27 soothsayer and have not seen a troll for sale yet.