Handcar Havoc

Handcar Havoc is a 2-vs-2 minigame found in Mario Party, Mario Party 2, Mario Party: The Top 100, and Mario Party Superstars.

Gameplay
Two teams have to race using handcars. On a curve, the handcar has to be leaned to the left or right so that it will continue without losing speed. In Mario Party and Mario Party Superstars, leaning too much will result in the team falling down into the lava. However, it is not possible to fall off the track in Mario Party 2 and The Top 100 (despite the former's Advice section in the rules suggesting players can). The first team to reach the end wins.

Mario Party / Mario Party 2

 * or – Lean handcar
 * (Repeatedly) – Speed up
 * – Brake

Mario Party: The Top 100

 * Left / Right: Shift weight
 * Mash : Accelerate
 * Brake

Mario Party Superstars

 * (Left and Right) – Shift Weight
 * Mash to Accelerate
 * – Brake

Mario Party

 * Game Rules – "Race the handcar in teams of two. The more the two of you press, the faster you will go."
 * Advice – "If you move left or right against the lean, you can go around corners without losing speed."

Mario Party 2

 * Game Rules – "Handcars careen down the winding mine track! The first team to reach the end wins!"
 * Game Rules (Mini-Game Coaster) – "Be the first team to finish this thrilling race between careening handcars to clear the game."
 * Advice – "Lean your handcar into the curves to corner more quickly without flying off the track!"

Mario Party: The Top 100

 * Description – "Work the handcar in tandem to reach the goal! Pump the lever to speed up!"
 * On-screen – "Work the handcar in tandem to reach the goal!"

Mario Party Superstars

 * "Race the handcars in teams of two. Be careful not to pick up too much speed on a curve. Fall into the lava, and you're out!"