Ludwig stole Santa Claus' presents, and Mario must defeat him.
Rejecting this mainly because of the weird implementation of the hypothermia gimmick. It almost feels tacked on. The explanation that it even exists is easy to miss, and it makes some areas like the line guide section at Chuck's Pond annoying. The biggest offender however is in the Ludwig battle, and my main reason for rejecting this. The hypothermia kills Mario during the victory pose making that level impossible to beat (at least from what I tried) and leads me to guess you either didn't test thoroughly enough, or added this in last minute. My suggestion would be to either remove this gimmick entirely or use it sparingly, as it really goes against everything.