Ruiz Jr. also believes Joshua will aim to regain the IBF, WBA and WBO heavyweight championships next Saturday by adopting a cautious in-ring strategy, Sky Sports News reported.
"I'm expecting that. But if he wants to bang, it's better for me. I love to bang because that's the fighter that I am," Ruiz Jr. exclusively told Sky Sports, six months after flooring Joshua four times and completing a memorable shock.
"December 7 we have to pressure, work the body, break him down. Especially his mentality.
"We've got to see where he's at because all the pressure is on him. The pressure isn't on me because I followed my dream, made my dreams come true.
"Of course I want more – I want the legacy of Andy Ruiz Jr."
Ruiz Jr had previously explained that his sparring partners were being "slick" in anticipation of Joshua trying to be elusive.
"People haven't seen me cut off the ring," Ruiz Jr. warned.
"I actually break them down even faster when they try to box me around.
"We all have a plan until we get hit, like Mike Tyson would say. I'm pretty sure he will want to box me around.
"One punch can change the fight. That's what happened on June 1. It might be a little harder than the first time. I've got to show my skills, my talent."
Ruiz Jr.'s only defeat in 34 fights came via majority decision to Joseph Parker in 2016, a verdict he still disputes. He insists that his style will always be a problem for Joshua.
"Especially me staying small. I don't think he likes fighting [against that style]," Ruiz Jr. explained.
"I don't think he's ever fought a short guy that pressures, and is pretty slick.
"I felt like I was boxing him around even though I was the shorter guy. I was counter-punching him. When he would throw, I would throw back with more punches.
"He saw something that he's never seen before.
"People said before, who would you rather fight: Joshua, Deontay Wilder or Tyson Fury? I always said Joshua because of his style.
"Styles make fights. His style was perfect for me to become the unified heavyweight champion."