Mario's EXTRAS: MARIO'S CHALLENGE is a video uploaded by TheAwesomeMario.
Here are the SECRET challenges that you missed!
Secret Floor 1: The Balance
In this floor, Mario tested each participant's balance with a beam and told them to climb to the next room. He also told them not to fall off because if they did, they would die. It appeared simple as claimed by a Lakitu who easily crossed the bridge in his cloud but near the end, a pistol appeared from the floor and shot him. Mario then added that the floor was full of traps. Dr. Pootis also tried the challenge dodging all the traps. When he saw that it was very high up, he called for his Magnus von Grapple but it accidentally landed on him, knocking him into the pit below.
Secret Floor 2: Mario's Tunnel of doom
Mario introduced the participants to his tunnel of doom which was filled with traps. He also reminded them to not die. Wario ran across the tunnel but pressed a button. It summoned a Mini Mario in a cage. Wario thought it was harmless but he was proven wrong when he got attacked. Waluigi nearby saw his brother's presumed demise and laughed it off as he proceeded down the tunnel. He soon encountered a cart on tracks and rode it. A challenge appeared: A target which was required to be hit before access would be granted. Waluigi tried firing at the target twice but it failed both times and instead, a ricochet into stopping the cart, and the releasing of a lantern which set Waluigi on fire. The cart shortly after crashed into the gate and exploded.