On the subject of mountains, let's get some Yeti's going! If you think about it, there's nothing more dangerous than a semi-sentient humanoid walking through a base!
And let's not stop there, oh no, let's make them multiply on an exponential scale! First there would be 20 (genetic diversity), with unique traits (domestic, aggressive, suicidal, deranged breeder). Then there would be
According to the equation where, for all natural numbers {1,2,3,4...1,000...}
x= new day's number of Yeti's
R= percentage increase per Yeti
I= increase in number
T= time of breeding
P= previous day's number of Yeti's
x= R*I*P*T*
This increase would be compound, thus resulting in an exponential growth of Yeti's
For non-exponential growth, substitute original number of Yeti's for x
-Penguin