Spike is a purple and green baby dragon who met Pooh and his friends in Pooh's Adventures of Thomas and the Magic Railroad after Twilight Sparkle rescued them from The Grand Duke of Owls. He is Twilight Sparkle's friend and assistant. His ability to magically deliver scrolls to and from Princess Celestia with his green fire-breath is featured in many episodes, as is his crush on Rarity.
- Spike met the FT Squad in The FT Squad's Adventures in My Little Pony: Friendship is Magic.
- Spike met Ash, Littlefoot, Simba, Sora, Mickey, Spongebob, Alex, Tai and their friends in Pooh's Adventures of Thomas & Friends: Misty Island Rescue.
- Spike guest starred in The FT Squad Meets the Hunchback of Notre Dame, and later will in The FT Squad's Adventures with the Winx Club.
- Spike will know all about Sunset Shimmer's Clone in Pooh's Adventures of The Fairly OddParents: Wishology: (Full Movie)
- Spike will make occassional guest appearances in The FT Squad's Adventures With Phineas and Ferb, and will officially guest star in The FT Squad's Adventures With Phineas and Ferb: Summer Belongs to You.
- Spike is best friends with Bertie and Luke.
- He is very great friends with Gusto Gummi, Soos and Mac.
- He is the "semi-biological" son of Barney the Dinosaur, mainly because he found his egg and decided to hatch it himself, like Horton did in his first book, Horton Hatches the Egg. This possibly explains Spike's purple skin and green stomach, and other things about him. He's also Bloodgood's step-son, and he calls Louis and Ronald McDonald his 'uncles'.
- Twilight, Sunset and Trixie transformed Spike into a Unicorn in the near end of The Magic of Friendship.
- Spike has partners with Mirage the Illusionist and Danny Williams.