Queensland's opponents know what Reece Walsh can do on a footy field, but when, where and even if he will unleash at the MCG remains a mystery.
The Brisbane talisman, known as "Reece Lightning" for his strike capabilities, is named on a six-man extended bench at No.18 for the Maroons in the second State of Origin showdown on Wednesday night.
Queensland must win to square the series and Walsh, despite not being in his best form in clubland, is an ace coach Billy Slater has up his sleeve.
It was put to Slater on match eve that there was "mystery" in the Blues camp about his plans for Walsh.
"Me included," Slater quipped.
"He is a wonderful player. No-one knows Reece better than I do.
"If needed I have no question he will do a great job in whatever position ... outside backs, in the halves or back at fullback.
"We saw what he was capable of in 2023 where he was probably the most influential player in that series. What a luxury for us to have a guy like Kalyn Ponga that can wear No.1 and Reece sitting there waiting for an opportunity."
For the MCG clash, Walsh has replaced out-of-form Broncos teammate Ezra Mam, who was cover in game one for the halves, but did not get on the field.
Walsh said last week he was ready for any role thrown at him, adding he would even play prop if asked. The sentiment has proven to be historically correct.
Current Maroons fullback Kalyn Ponga debuted in Origin in 2018 in a roving lock position and had a brilliant 52 minutes to almost grab victory for Queensland.
Maroons captain Cameron Munster played alongside Ponga in that match and added further mystery to the Walsh role.
"They both play fullback but Kalyn is that bigger body who can definitely handle the middle," Munster said.
"Reece can handle the middle but probably doesn't make a whole lot of tackles in the front line.
"There are ways to get certain players into a game. Who knows? I am sure Bill and the coaching staff have got a plan. I will leave it at that otherwise I will put my foot in it."
Ponga is in the position Walsh held for five Origin matches in 2023 and 2024. He said the Broncos whiz was capable of anything if given an opportunity.
"When he goes after it, he is someone that is pretty fearless," Ponga said.
"There's all the attributes with his skill, but his mindset, we saw it last year in the (NRL) finals series, he was on another level.
The pair are great mates, despite competing for the No.1 position.
"There is a mutual respect that whatever is best for the state and whatever Billy thinks is best for the team, we understand that," Ponga said.