Skull Kid

Skull Kid (スタルキッド Stalkid?, ) is a recurring character in the Legend of Zelda series. A member of the Skull Kid race of creatures, the Skull Kid is a mischievous being who takes delight in playing tricks on others. He serves as the primary antagonist for the majority of The Legend of Zelda: Majora's Mask, and it is generally accepted, though not explicitly stated, that he makes his first appearance in The Legend of Zelda: Ocarina of Time.

Majora's Mask/Pokémon crossover (time paradox)
The Skull Kid was first encountered in the Lost Woods along with his fairy partners in crime, Tatl and Tael. He was seen wearing a scary mask who ordered his fairies to ambush Epona, causing her to be scared and rear back, rendering Link unconscious. He stole all of his possessions, most notably his Ocarina, and ran off with a dastardly Epona. Link pursued them through a large, hollow tree and fell down the rabbit's hole to Termina, where he stated that he killed his steed since she never listens to him, then he curses him into a Deku Shrub, laughing that it "looks good on (him)." Finally, he disappeared, and then Tael got separated from his sister, Tatl, who stuck with Link throughout their journey, along with Zelda II and her gathering Pokémon.

He was soon seen again at the top of the Clock Town Tower as the menacing Moon he created was crashing down. Still in his Deku form, Link and the three Johto starters attacked him and Tael in point blank range, until Link received the Ocarina Skull Kid stole. With that, he was able to reverse time and start back on the first of the three days to save Termina.

Skull Kid was seen one last time on the same night at the top of the Clock Tower, and it was revealed that by exposure to the accursed Majora's Mask, he got possessed by the evil deity, while using him as a puppet. He laid unconscious after that, and Tael stayed behind, while Link, Tatl, Zelda II, and her partners pursued the demon inside the Moon. Sadly, by the time they've accomplished their mission and when the Moon was destroyed, he never lived to see another day, as he was captured and soon executed via guillotine by the scared townsfolk. He wasn't the friend that Tatl and Tael described him as, ever since they found and befriended him when he was lost in the woods during a massive rainstorm; they didn't know each other long, but it was still tragic. Nevertheless, at least Link, and eventually Zelda II, would be new friends to the fairies under the condition they'd be watched over at all times.