Tom riddle first encounter with Dumbledore destroy his trust in the wizarding world ,as the headmaster burn his belongings to "show what happens to mudbloods who don’t know their place " .
Despite that ,Riddle accept the invitation to Hogwarts ,ending up a model student in Slytherin.Being charismatic and talented ,he manage to crush his wannabee bullies and over the year cultivate a small group of friends and even convincing them of blood purism foolishness .He even gets a reward for finding the Heir of Slytherin ,Hagrid ,whose acromentula murdered Myrtle Warren . But even his excellent grades do not open him the door of the Ministry .
The jobs are reserved for purebloods ,with half-bloods or those of lower purity never hired .He end up with no choice than borgins and burke ,simmering in bitterness at his wasted potential ,before deciding to hone his craft and try again ,when his mastery shall be obvious .
But Dumbledore ,having became Headmaster ,refuse him the job of DADA teacher despite him having gone above and beyond the stated requirements ,only to engage a pureblood moron whose father backed Dumbledore ascension to supreme mugwump .
Furious ,Tom become obsessed by ending the blood purist hold on wizarding england and their blood apartheid .With the help of his school friends ,he forms a terrorist cell to enforce muggleborns and half-blood rights .
The war take a decade,but the decadent Ministry slowly fold ,even pushing a desperate dumbledore to make his own counter-terrorist group.Riddle even receive Elixir of life from the secretly sympathetic Nicholas Flamel .
But Snape arrive with a disastrous prophecy .Of a boy ,who shall be able to rival him,and grow up with the potential and the desire to destroy the muggles thanks to an engineered nuclear war ,and who can only fall from from his hand . Seeing the boy as too dangerous to be allowed to live ,Riddle immediately does his utmost to find the scourge house .
Thanks to Pettigrew ,that ends up being trivial.Riddle bust down the door of Godric Hollow ,kill James Potter ,stun Lily as Snape had asked and sling a killing curse at Potter ...only for the curse to rebound and only escaping death (becoming a wraith instead)thanks to the elixir of life ,while Lily die due to the explosion .