"A mountain range near Grass Town. Somewhat treacherous and definitely tall, climbing them is not an easy task."
The Imposing Mountains, situated a few hours' walk from Grass Town, is, as it namesake states, quite imposing even before going within it. With mountains stretching across one's entire line of sight, and peaks that reached up far into the sky, it is not somewhere that ordinary people visit regularly. However, it is also said to be the keeping place of a great treasure.
This is proved correct, as it is the keeping place for one of the 4 (at the time) Odd Diamonds. As such, the Dimensional Guard dissuades people from visiting there, and quickly punishes anybody who dares to impose upon this place - often with death.
Being one of the keeping places of the Odd Diamonds, it is almost necessary for humans to go here in order to have a chance at finding out how to get home.
All four had to struggle with some of the Dimensional Guard trainees - Darwin did meet a fully-fledged Dimensional Guard, but retreated quickly.
Of these four humans, Darwin was the only one successful in claiming the Odd Diamond and dealing with it's guardian - an incredibly powerful robotic Articuno, whom even with his partners at the time could not equal it's power.
Name: Articuno Origin: DN1; Unknown Forms: Articuno P2000 Possessions: Guarding an Odd Diamond Strong Point: Combat in general Weak Point: Struggles to concentrate when enraged
The guardian of Imposing Mountain's Odd Diamond is, somewhat ironically, a huge robotic Articuno, a legendary bird of ice.
While it is unknown who exactly designed it, it seems highly probable that it was one of the Creator's creations - it being a robot might even go as far as to assume that it was a prototype creation for a more powerful creation.
An interesting point is it's creation in Dimension Number 1 - while nothing was learned about the mechanical legendary, it could possibly be taken that the Articuno was created before even Dimension Number 2 itself had been.
Whatever the case, it's design made it completely loyal to it's duty of guarding the Odd Diamond. As the statistics show, it was certainly more than up to the task of doing so.
Despite being more than a match for Darwin and his partners, Oliver and Ann, the guardian eventually fell to the team's onslaught.
It is unknown if the guardian was to be rebuilt.
With the occurrence of the Dimensional Shift, the Creator's radical recreation of Dimension Number 2, the Imposing Mountains were effectively destroyed.