The midfielder spent the second-half of the previous campaign with the same club, in his home nation of Slovakia, making 14 appearances and scoring three times.
The 19-year-old joined Wolves’ Under-18s in 2014 and had been a regular in Scott Sellars’ Under-23s side prior to his move in January.
Herc signed a fresh deal at Molineux back in October, extending his time with the club until 2020.