Not the worst trades but trades that ended up being lopsided and had the other team benefit greatly from it making the GM look brilliant. I wouldnt include the Gretzky trade because the Kings knew they were going to vastly improve after that. I mean trades like Francis to Pittsburgh, or Goring to NYI. Or even the Esposito package that went from Chicago to Boston.
The Habs getting Ken Dryden from the Bruins for bpretty much nothing. Detroit getting Kris Draper for $1. The Habs getting Russ Cortnall for John Kordic (R.I.P). There are countless others. unless you consider these "worst" trades.
Dryden and Alex Campbell to the Bruins for for Guy Allen and Paul Reid on June 28, 1964. Other than Dryden none of them made the NHL. Campbell played 1 season in the IHL, Allen played 3 seasons of minor pro and Reid never turned pro. Dryden would be the Big Bad Bruins nemesis. Naslund for Stojanov is another one to go
So, the worst trades in reverse... The best trades are ones that benefit both teams, like Newsy Lalonde for Aurel Joliat.
Bruins get: Cam Neely and the Canucks first round (third overall) pick in the '87 draft. Canucks get: Barry Pederson Yes.
After the 1972-73 season, Bernie Parent's NHL rights, held by Toronto while he was in the WHA, were traded to the Flyers (along with a pick -- Larry Goodenough) for a 1973 1st round pick (Bob Neely) and Doug Favell. The Flyers won the next two Cups.