However, after an incredible season it was Huddersfield Town who secured the third and final promotion spot thanks to Christopher Schindler's winning penalty in the 4-3 shootout.
Hefele missed Huddersfield's second penalty as Ali Al Habsi plunged to his right to save, but Liam Moore blazed Reading's fourth high over the bar.
Speaking post-match, Wagner admitted the Aussie midfielder, and club's Player of the Season, was the "heart" of Huddersfield's game and labelled Mooy as his side's "outstanding" player this season.
The victory sends the Terriers into the top flight for the first time since 1972, when they played in the old First Division.
But the huge boost to their bank balance pales in comparison to the lifetime of memories Huddersfield's players and supporters will take from their promotion triumph and next season's unexpected place among the Premier League aristocracy.
"But with an open mind it can be achieved, though I never thought it would be possible".
Premier League football could lure some of the bigger names to Huddersfield Town now however, but who these recruits will be we shall have to wait and see. "We only wanted to play this season to our limits, and now we know where our limit is". Experience is important - but if you have passion and desire you can do it and I'm very proud.
The Australia worldwide helped to pull the strings in midfield for the Terriers as they took on Reading in the Championship play-off final.
Dean Hoyle, Huddersfield Town chairman, said: "When I took over in 2009, it has got harder and harder".
Habsi thanked his fans in United Kingdom and Oman and said, "To all our dear fans and supporters, I thank you from the bottom of my heart for being with us throughout the season. They'll probably have to leave me alone for another 24 hours".
"We stuck to it, we had some bad runs but we came back strong and got ourselves into the play-offs".