Excellent work.

A few thoughts-my understanding is that the phenomena hasn't properly started yet in our near area-but you may have used a timey-wimey solution around that. 

As to being a one prize per trip-thats also what I and my team believe.

Using sex for the troll toll?  Hilarious.

From other sources: I one asked what's the big deal with trolls?  Why use them when meaty boys like dragons are available-and generally friendlier.  Answer was that trolls due to high earth element are very very durable, and particularly resistant to magic.  That's why the asians use physical beans and rice and with the noise to drive them away (the plant's seeds contain very high life energy.)