Alberich

Here’s my take on Alberich (or Alfrikr, or Andvari, for the original Norse version), who is, in Germanic mythology, a Nibelung/dwarf possessing (or guarding) treasures and magical artifacts, and whose name is said to come from the term "king of the elves" (elbe, "elves", reix, "king"). Although he has his origins in Norse mythology, he appears in the medieval Germanic epic called the Nibelungenlied, and other European chivalry sagas. But Alberich was popularized as the main antagonist of Richard Wagner's operatic tetralogy The Ring of the Nibelung. In the most notable iterations of the character, he is a dwarf who finds himself dispossessed of his gold and places a curse on it, so that no one but himself may enjoy it. But I will tell different versions of his story backwards, all the way back to the original Norse myth.

In The Rhinegold, the prologue to Wagner's operatic tetralogy, Alberich is the first troublemaker. While still just another Nibelung, he ventures from the underworld Nibelheim to the waters of the Rhine, to woo the three Rhinemaidens, seductive and mischievous undines. But the ugly and lecherous dwarf inspires nothing but mockery from the Rhinemaidens, who, with their agility and slippery skin, easily elude him when he nevertheless tries to seize them in frustration. But the rays of the rising sun then pierce the waves to touch an imposing deposit of gold atop a rock, which turns out to be the Rhinegold, and which the undines must guard. Knowing that only one who renounces love forever can seize it, the Rhinemaidens believe they have nothing to fear from the lustful Nibelung, and reveal him everything about the gold. They tell him, in particular, that a ring forged from this ore would give its wearer "the riches of the world." But the undines have mistaken love for simple physical desire : now embittered and vindictive, Alberich curses love and steals the gold, before the panicked Rhinemaidens.
Back in Nibelheim, the sinister dwarf forges the Ring, which allows him to detect gold veins, and which also seems to be able, in a certain way, to compel others to his will. The Nibelung then proclaims himself king of the dwarves, whom he subjugates and tyrannizes, forcing them to work tirelessly for him alone, solely to increase the amount of gold in his possession. Even Mime, Alberich's own brother, is forced to forge a helmet from the gold, following his new master's instructions. What Mime does not know is that this helmet, the Tarnhelm, gives its wearer the powers of invisibility and metamorphosis, which Alberich abuses to further terrorize his brother and his peers, lashing them with his whip without them being able to see him. But then come Wotan/Odin and Loge/Loki, who plan to steal the Nibelung's treasure in order to ransom the goddess Freia – guarantor of the eternal youth of the gods –, who is being held hostage by the giants Fasolt and Fafner. The cunning Loge hides his intentions from the dwarf, who goes so far as to threaten the gods with his newly acquired powers, saying among other things that their women, who have denigrated him, might well find themselves forced to sate his lust. But, questioned by Loge on what he could do if someone stole the Ring and wanted to use it against him, Alberich explains the power of the Tarnhelm ; the demigod says he doesn't believe him, and pushes the proud dwarf to demonstrate it to them. The Nibelung then transforms into a terrible giant serpent, but after feigning terror, Loge asks him if he can also change into something very small, to better escape his enemies. Alberich then transforms into a toad, but the demigod and Wotan seize him, and bring him to the surface.
Wotan then forces him to give him his treasure, and Alberich, who imagines he can keep the Ring, complies despite his anger. Thanks to the Ring, he calls his servants from a distance, who emerge from the depths of the Earth with all his gold, and place it before the gods and their humiliated master, who angrily chases them away. But Wotan notices the trinket, and orders the Nibelung to give it to him as well. Upset, Alberich refuses, declaring that he would rather die than give him the Ring, but the one-eyed god snatches it from his finger. Now free, but destroyed, the dwarf places a curse on the object : if he cannot enjoy it, no one will ; those who do not have it will despair of seizing it, and its possessor will draw the murderer to him, until the Ring returns to its creator. Alberich then returns to Nibelheim, laughing in defiance.
...And I don't have room for the rest of the story...