Examples of The Other Darrin within Adventure Time.
Main Series
- All the voice actors from the original short, with the exception of John DiMaggio, were replaced when the pilot became a fully-fledged series. But the most interesting example is that Finn's voice actor (Zack Shada) was replaced by his younger brother Jeremy, because the elder had hit puberty and wasn't able to do his Finn voice. As Jeremy started going puberty too, rather than replacing him, the writers decided to simply have Finn age alongside his actor.
- Princess Bubblegum is played by Paige Moss in the pilot and Hynden Walch in the series.
- Ice King was played by John Kassir (The Cryptkeeper, Deadpool, the replacement voice for Buster Bunny when Charlie Adler left) in the pilot. In the series, Tom Kenny plays the Ice King.
- In the pilot, Lady Rainicorn was voiced by Dee Bradley Baker and spoke nonsense. In the show, her voice actress is Niki Yang (the same Niki Yang who plays BMO) and the nonsense was replaced with fluent Korean.
- Tiffany was voiced by Vincenzo Rauzo in his first appearance in "My Two Favorite People". He has been voiced by Collin Dean in the character's subsequent appearences.
- Ghost Princess is played by Pen in "Loyalty to the King" and Maria Bamford in "Ghost Princess".
- In the video game, Marceline is played by Jessie Seely instead of Olivia Olson. Granted, the difference is barely noticeable.
- In "Davey", to make his disguise more authentic, Finn changes his vocal chords to a more adult tone of Davey Johnson.
- In his first appearance, the Cosmic Owl has a feminine-sounding voice provided by Finn's actor, Jeremy Shada. In his next speaking role, M. Emmet Walsh took over the role and gave him a much more masculine, older-sounding voice.
- John DiMaggio voiced Jake's brother Jermaine in "Crystals Have Power", but in "Jermaine" he's voiced by Tom Scharpling of Steven Universe.
- Huntress Wizard is voiced by Maria Bamford in "Reign of Gunters", but in "Flute Spell", she's voiced by Jenny Slate, fresh out of Zootopia.
- Melissa Villaseñor briefly takes over voicing Slime Princess in "Elementals" in place of Maria Bamford.
- Felicia Day replaced Lena Dunham as Betty for the Elements mini-series.
- In a voice director variant, Keythe Farley was originally the voice director for the first half of season 1. He would be replaced by Collette Sunderman for the remainder of season 1 and all of seasons 2-4 until she herself was replaced by Kent Osborne as voice director from season 5 until the end of the series.
- In "Five Short Tables", Prince Gumball is voiced by Keith Ferguson instead of Neil Patrick Harris. In the Fionna and Cake miniseries, his voice was replaced for a second time by Andrew Rannells.
Adventure Time: Distant Lands
- In "Obsidian", Erica Luttrell replaces Rebecca Sugar as Marceline's mother and Audrey Bennett replaces Ava Acres as young Marceline.
- In "Together Again", Corrine Kempa plays Life (she was previously played by Hynden Walch in the shorts) and Tiffany goes from being voiced by Collin Dean to Aryan Simhadri.
- In "Wizard City", Bufo is voiced by Bill Hader instead of Steve Little/Tom Kenny. Speaking of Steve Little, Mace Montgomery Miskel takes over the role of Peppermint Butler's post-Dum Dum Juiced self Pepper Mint. However, Little still voices the original Peppermint Butler.
Adventure Time: Fionna and Cake
- Jinkx Monsoon replaced Justin Roiland as Lemongrab starting with this series, due to Roiland being charged with domestic abuse in 2020.
- Prismo is voiced by Sean Rohani instead of Kumail Nanjiani. According to Nanjiani, this was due to a miscommunication with his agent, who turned down the role on his behalf and never informed him of it.
