

Natla thinks that Avalon is the same as Helheim, the underworld. It is impossible to intrude without Thor's hammer, called Mjölnir. Probably this was the relic that Lara's father was looking for in Thailand?
Lara's father collected all of Bhogovati's treasures and destroyed every hint showing how to get to Helheim – however he left a key for Lara that only she can understand. He must have found something terrifying and dangerous to destroy such a unique archeological site.
Looking through her father's photographs Lara found out the location of Thor's belt in Central America and the hammer's place, hidden somewhere between Greenland and Norway. Zip doesn't understand, how come that Lara won't give up on searching even after the murder of Alister but she is certain about finding out the killer's identity by investigating further.
Thor's hammer is one of the most powerful weapon in human mythology. It is strong enough to destroy Jörmungandr, the immortal demigod while the world burns in the final battle, Ragnarök. Lara doesn't care about power and authority, she just needs to find answers – the truth behind all the myths of legendary relics.
Eventually Amanda helped Lara a lot by digging out the Queen of Atlantis. Since Lara has Thor's hammer she is now strong enough to interrogate Natla about the whereabouts of Helheim and to erase that place from the world…
The Midgard Serpent must be a metaphore for an enormous appliance and even Lara's father has played in mind what would happen if he opened Helheim though he was desperately looking for Lara's mother. This is a risk that Lara must take to find out the truth.