Hammer Bro's rise to become a Mario Party player.
After Hammer Bro is defeated by Toadette (since that's who I completed Mario Party 8 with) Hammer Bro begins to doubt Bowser and join the Mario and his friends to compete in the party tent. This all takes place during Mario Party 8.
After being defeated, Bowser scolded him from above and jumped down to Toadette, who was waiting for him at the start of the board. Hammer Bro walked off the blue space he landed on and toward the edge of the board, so he could watch the final battle between Toadette and Bowser. He watched, his heart racing to see if Bowser wins and takes the star rod from Toadette. However, as usual, Bowser is defeated and sinks into a vortex as Toadette celebrates her victory, then catching glimpse of Hammer Bro. Hammer Bro saw her look at him and quickly fled, fearing Toadette will attack him next. Toadette flew toward him and unlike what Hammer Bro thought at first, she offered him a ride back down. Though refusing to ride behind her, he got behind anyway and they traveled back down to the festival. Hammer Bro got off first and walked off to the side, while Toadette was praised with defeating Bowser. When Mario got up to shake with Toadette, she ran off to Hammer Bro, due to his sad look.
"Hey, what's wrong with you?" Toadette asked him. Hammer Bro looked up around the festival and saw how happy everyone and how much better it would be to not help out Bowser. Toadette saw where he was looking and came to a conclusion. She ran off to Mario and not too much longer, they (Mario, Luigi, Toad, Yoshi, Wario, Toadette, and Ballyhoo) gathered around Hammer Bro. Mario held out his hand to Hammer Bro, who looked up to notice it. Unsure at first, he looked at everyone's face to see them with trusting faces. He grabbed Mario's hand, to where he pulled him up to his face. Mario smiled. "So you want to be in this festival, you'll have to work your way up." He said. Hammer Bro nodded, excited about this kind of chance. Luigi walked up beside Mario and waved for Hammer Bro's attention. "But first, you got to work up to become one, because you know, first timers aren't the best." He said, once Hammer Bro looked at him.
Mario then walked in front of Luigi to get Hammer Bro's attention again. "So follow me to where your training will begin." He said and began walked off toward one of the tents. Before Hammer Bro began following him, Luigi grabbed his shoulder and waited there until Wario had walked off. "Just to let you know, there's a good change you won't win against Wario, because he cheats, and it's annoying". Luigi said quietly to Hammer Bro. Hammer Bro looked at Wario and nodded. After that, they followed behind Toad, who was in the back behind Toadette.