Shad Markly is a male Mobian cat who appears as the main antagonist of Eli's Wonderful Life. Shad was without any real friends, so in order to gain friends, he told lies about Eli J. Brown the Hedgehog such as how he was a thief and was in love with rag dolls. Some people actual fell for Shad's lies, some did so temporarily and some permanently. Eli's last encounter with him was with a duel and while Eli did win the fight, he didn't win back any friends he hadn't won back already, leading him to run off plotting revenge. Ten years later, Eli wished that Shad never existed, and a White Cloaked Figure showed Eli what life would be like if Shad was never born, and while the betrayal of Eli's friends were erased along with Shad, it also erased what happened with Eli where he saved his sister, adopted Renae Brown, and became a TUFF Agent. Upon seeing how horrible life would be for his new friends, Eli wished his old life back and when he awoke to find everything back to the way it was, he was relieved and had learned to finally move on from the past. It turned out that Shad had realized that Eli was right about what he had said to everyone and had realized he had gone too far. After sometime, Shad couldn't get his guilty feeling out and thought that he would explode if he didn't confess to everyone who didn't permanetely reform. So he admited to his lies to Tom, Catano, Travis, and Luis, but upon telling them the truth, it didn't get them back on Eli's said, but it did cause him to lose them as friends himself (which he actually was expecting and felt ready to accept this punishment). After this, Shad was scared that if he encountered Eli and his new friends, he'd make his new friends turn on Eli.
In the present, Shad had moved on from telling lies and was living as a normal citizen. He was shown working at a fair ground at a ball toss game. It was here were he met with Eli again after ten years and Shad told Eli what happened when he did confess to his lies and why he hadn't spoken to Eli for the past ten years. Eli had forgiven him for his lies, seeing how truly sorry he was, and helped Shad to make new friends.
- Shad is chronologically the first antagonist Eli encounters.
- Shad is very similar to Diesel from Thomas & Friends as they both had told lies about a protagonist to make their friends turn on them (Duck for Diesel and Eli for Shad).
- In Wobbley's fanfiction that served as a continuation to Eli's Wonderful Life, Shad wrote a letter apologizing to Eli for lying to him. This is however considered non-canon as Eli-J-Brony's intent on Shad is that he moved on. But eventually, Shad did canonically reform.