The Underworld

So this will take some time to explain...  In Book One, the Morianders and Nibel and a few others realize that the door to the Underworld is now.  For the Morianders and Charlie, this is a big surprise.  The Underworld is fairly complicated, delightfully so.  There are 8 levels which are the reverse of the 8 laws.  For example, level one, is the land of the Unjust, Level two is the land where there is no compassion, etc.  (after life, souls would go to the various levels if they have issues with one of the corresponding 8 laws.)  The 8th level is the land of Chaos.  This is the most dangerous level of all. 

In Book Three, the main characters will travel down through all the levels.  You're going to love Book Three.    (remember now, Books, 3,4 and 5 are already written)  - so there is hope !!!
In the Chronicles, the Underworld is intertwined with the three roots of the magic tree, Drasil.  I use nine worlds but they differ to some degree with the Norse mythology nine worlds.  In the Chronicles, the nine worlds are: 

1.  World of Ice and Cold
2.  World of Fire
3.  World of the Light Elves
4.  World of the Dark Elves and Goblins
5,  World of the Dwarfs
6.  World of the Gnomes
7.  World of the Giants
8.  Heart of Heavens
9.  Medelia, World of the Humans

After the World of the Humans was created, the doors from the nine worlds that opened to the Underworld were sealed shut.  Thus, there was no way that anyone from the nine worlds could travel to any other world.  After the Betrayal, however, all nine doors were opened.  There is one door in each world that leads down to the Underworld.  Secret passages in the Underworld lead to each of the nine worlds.  The door to the Underworld in Medelia - the World of the Humans - is deep inside the Poisoned Forest near the city of Myrkland.

Nibel, of course, came from the World of Dwarfs.  His brother Ragand, who was much weaker in both the mind and the body than Nibel, did not have the strength to make the entire journey to the World of Humans.  Nibel leaves him !!!!  - a big mistake - Nibel found Toad in the Underworld.  He took him to the Medelia and by Nibel's alchemy, he turned Toad into a toad with human characteristics. 

In Medelia, the door to the Underworld, as I mentioned, is in the Poisoned Forest.  Now there is good reason why the Poisoned Forest is named such...the forest is filled with pockets of deadly lethal gas.  The pockets of gas were formed from the lizard's fiery breath.  So, even if someone knew where the door to the Underworld was, the journey there would be hazardous at best.

In Book One, the Forest Gnomes, including Niss, Nibel the dwarf and a number of Goblins have successfully made the journey from their respective worlds up through the Underworld to Medelia.