The Terriers return to Molineux for the first time since a goal from Izzy Brown, in April, 2017, clinched a place in the Championship play-offs.
Town subsequently went on to win promotion at Wembley before beating the odds once again last May by avoiding relegation.
Wolves, promoted last May, sit 11th in the table and are firmly on course to follow Huddersfield, Brighton and Newcastle by beating the drop in the first 12 months after arriving in the top flight.
“I believe Wolves are not a normal promotion team,” said Wagner, who is without the suspended Mathias ‘Zanka’ Jorgensen and injured Chris Lowe tomorrow.
“They are on a different level to teams that got promoted in the past.
“They invested money, but they did it smartly. The play very well and are consistent in their personnel. They got promoted by 10 points last season.
“Their main threat is that everyone knows what they have to do. They consistently play the same players.
“They have a lot of consistency and quality. They have players who are hungry and greedy.”
Town head to the West Midlands fresh from a week of warm weather training in Marbella, a trip Town have made three times in as many years under Wagner.
He said: “The trip was fine. Everybody is healthy, but it helped us come together as a group. Not only the players, but the backroom staff, and the children as well. The third time we brought all the family to the training camp. We were able to train and have some family time together as well and that was what we needed after the first game. This was for us a great scenario because the weather conditions were good.”