- Cash Cow Franchise: This should come as no surprise considering what both Mario and Sonic are on their own, even more so considering that they're competing in the biggest sporting event in the world.
- Fandom Nod: Introduced in Mario & Sonic at the Sochi 2014 Olympic Winter Games, an event, Figure Skating Pairs, allows the player to select a male and female character to be paired with each other. Guess what fandom practice this promotes.
- The Other Darrin:
- In the original installment, Peach was voiced by her former voice actress Jen Taylor, but has been voiced by her current voice actress Samantha Kelly from Vancouver 2010 onwards.
- London 2012 onwards utilizes the new Sonic voice cast introduced in 2010's Sonic Colors (with returning voice actor Mike Pollock recording new lines for Dr. Eggman). Furthermore, this is also the first Mario and Sonic game where Kenny James replaces Scott Burns's archived recordings as the voice of Bowser (although he did voice Dry Bowser in Vancouver 2010).
- The first two installments are also the primary place to hear Vector voiced by Dan Green, replacing Carter Cathcart after he stopped working for 4Kids.
- Rio 2016 is the first game in which Matthew Mercer takes over the role of Espio from Troy Baker, which considering the actors involved was probably fine.
- It is also the first canonical game to feature Colleen O'Shaughnessey as Tails, although his previous voice actor Kate Higgins still provides the voice of Wave in the game.
- An interesting inversion occurs in the same game with Wendy, Larry, and Ludwig, who are once again voiced by Lani Minella (Wendy and Larry) and Mike Vaughn (Ludwig) respectively after receiving different voice actors in Mario Kart 8 (Ashley Flannagan for Wendy, Michelle Hippe for Larry, and David J. Goldfarb for Ludwig respectively).
- Due to Chikao Ohtsuka's death from ischemic heart failure in January 2015, Kotaro Nakamura replaced him as Eggman for Rio 2016, effectively making him the de facto voice of the character.
- What Could Have Been:
- Silver the Hedgehog and Donkey Kong, who are playable characters in the second game onwards, were planned to appear in the first one in the same capacity. Birdo and Jet the Hawk were to appear in the first game as playable characters too, but they ended up in the second game as a VIP audience member and a Festival Mode rival character, respectively.
- The Olympic Games games also caused a What Could Have Been on an unrelated Sonic game: Sumo Digital thought up of the possibility of having Mario as a guest character for the Wii version of Sonic & Sega All-Stars Racing (for reasons that should be obvious) but didn't go ahead because of the mere existence of these games, feeling that Sega would be cash-cowing both Mario and Sonic too much otherwise. (This also had the side effect of letting Microsoft go unopposed with their own guest racers for the Xbox 360 version, not to mention the fact that Sonic has been playable in the Super Smash Bros. series alongside Mario since Brawl, which was released about 2 years before All-Stars Racing).
- Swimsuits for Peach and Daisy were planned for the first game, but were scrapped by Nintendo. They eventually got their swimsuits in the London 2012 game, although swimsuits were also planned for all characters, but the idea was rejected by Sega since it would be mean having Sonic's shoes removed.
Trivia / Mario & Sonic at the Olympic Games