Survival Relay

It's one of the 3 playable modes on Survival mode. It consists on a 2 or 3-lap race (it depends on the players' choice), in which 2 or 3 SCR-GP units (or the rival team) will try to overtake or attack the player on-screen before the other players' turn.

How it works
The 2, 3 or 4 players may choose one of the 3 ways to play this mode: (Note: the form they choose will can change the number of laps the race will last)
 * 2 players vs 2 SCR-GP units
 * 3 players vs 3 SCR-GP units
 * 2 players vs 2 players

Once they've chosen one option they may choose any circuit of the available, and then they get to choose their Extreme Gear (except SCR-GP or SCR-HD units). The leader is the only one who gets to pick an Extreme Gear for the rest of the race, the others will have to use the chosen Gear in order to compete.

The race starts just like any other race in the game, and it even develops the same way as a normal race. The only difference is that when the player is near the finish line, the character needs to run into the next character so the other player gets to play and a lap is completed. The race will continue until the character on-screen is either overtaken or attacked by the rival team, finishes the race without losing or the 3rd character gets it's turn, and subsequently finishes the race. In addition, the number of rings collected and the Gear parts won't change even if one player's turn has ended.

Trivia

 * Due to it's mechanics, and the fact that there can be only one Extreme Gear per team, Dr. Eggman can only compete in a team if a bike is the chosen Gear of the team.
 * It's the only Survival mode that shares the most similarities to a normal race in the game.