Just a quick little drabble challenge response, on how Voldemort started looking the way he did. I don't own anything, and that is definitely not Voldie's nose on the wall behind me.
The first time Potter and his friends defied him was when he lost his hair. Lucius Malfoy had given him some products to use in his hair as a gift. Why, Voldemort didn't know. Perhaps the man was trying to get into his bed. It wouldn't work; Voldemort had sacrificed that bit of his anatomy as part of an immortality ritual many years ago. Still, he was curious as to why the young Death Eater loved this so much, and he used it one morning. It didn't seem to be doing anything, until he pulled his hands down and a large clump of hair came with it. Malfoy was subject to many Crucio's that day. He only stopped when Pettigrew informed him that it was a prank by Potter, Black, and the mudblood Evans; aimed towards Lucius. He still got the occasional Crucio over the next few weeks.
The next time was also in the shower. Somehow, Potter and his friends had gotten into the plumbing and tried to poison his Death Eaters with a bleach potion. Fortunately for each Death Eaters that didn't get Crucio'd, Voldemort was the only one affected and his safety precautions kept him alive and relatively pain-free. It hurt less than the Cruciartus anyways. But he would always have the pale, bone-white skin and bloody red eyes. One Death Eater, Snape, was smart enough to comment that he looked more intimidating that way.
The last time was on Halloween, 1979. An attempted raid, led by the Dark Lord himself, was countered by aurors. James Potter was the only one foolishly brave enough to stand up to Voldemort. Their duel only lasted a few minutes, but many would later comment that it was the greatest display of skills they had ever seen. When the aurors had rescued the target, Potter sent a stream of curses and hexes before apparating away. Voldemort shielded all of them, except for a weak cutting hex that hit him straight in the face. Staring at his severed nose, he resolved to kill the Potters on Halloween in revenge.