20km Race Walk

20km Race Walk is an Athletics Event that appears in the Nintendo 3DS version of Mario & Sonic at the London 2012 Olympic Games. The objective of the event is to be the first to cross the finish line with the shortest time. The event has a starting World Record of 1:17:16 and Olympic Record of 1:18:59.

20km Race Walk appears as the second challenge in Heroes Episode 3, A Rainbow in Fog, in the Story Mode in which Sonic must beat Fog Imposters of Mario, Luigi and Tails. It also appears as part of Challenge 2 in Heroes Episode 5, The Promise to Toad, where Sonic must beat the Fog Imposters again in it along with Modern Pentathlon and Marathon. It is also the challenge in the Final Episode The Grand Showdown, in which Sonic must beat Bowser when he is powered up by the Phantasmal Fog.

Gameplay
The event begins in the final 2km of the race at one hour in, with a sped up timer being used for the part of the race that the player must complete. The player must use the stylus to slide left and right on the Touch Screen in time with the music to control their character's walking pace. An example of the pace will be given while the character continues walking before the player has to start sliding themselves. The first piece of music is the slower-paced Three Marches Militaires, Op. 51, No. 1 by Franz Schubert, which changes to the faster-paced Can-Can music partway through the event. The player must not go too fast, or they will be penalised and stopped for a short amount of time for running. The player will also stop for a briefer amount of time if they go slightly too fast.

Omochao appears in the top left hand corner of the upper screen and comments on the player's pace. He makes comments of "Perfect! Perfect Pace!" when the player keeps sliding at the right speed, "Too fast!" with a red card when the player is sliding slightly above the right speed, "Bad! Faster, faster! Slide faster!" when the player is sliding too slowly and "Red card! There's a penalty for running!" when the player slides too fast.

Controls
1) Walk: Use the stylus to control the tempo by sliding ⇔ on the Touch Screen.