Factual error: At the end of the movie, they show a bunch of ducks flying. Those are not ducks, they are geese.
Factual error: The so-called Icelandic hockey team is not speaking anything close to Icelandic.
Factual error: Throughout the movie, there are several times that players are bodychecked who are nowhere near the puck. In hockey, a player cannot be checked if he/she is not in possession of the puck. This means that the player has the puck on their stick, or has passed it but it hasn't yet been picked up by another player. If a player checks someone who is not in possession of the puck, they should be assessed a 2-minute minor for interference.
Factual error: Russ Tyler's game-tying goal at the end of regulation in the championship game is preceded by several implausibilities and rule infractions that effectively would have nullified the goal. Firstly, not only is it against the rules to switch jerseys with another player (he is visibly wearing Goldberg's jersey), but there is no way he could have put on all the goalie pads in the 30-second time out. Secondly, he removes his helmet. When a goalie's helmet is removed during play, the game will be stopped and the goalie will be given a delay of game penalty if he intentionally removed it. And lastly, he skates all the way to center ice to take his shot. Not only do the players for the supposedly highly talented Iceland team not pick him up at center ice to defend his shot, instead allowing him to swap sticks with a teammate and take a wide open shot, but if a goalie with possession of the puck reaches center ice, play would be stopped and a face off would be held in the goalie's team's defensive zone.
Factual error: When Ken Wu dropped his gloves and went after the Iceland player, he was given a 2 minute roughing penalty. International Ice Hockey Federation Rules state that at the very least he would've been assessed with a 10 minute misconduct, or he would've received a match penalty, and would've been ejected from the game.