More gamer-speak ahead (which is mostly what tends to show up there, especially in this series).
When I sat down to write my own drafts of the missing seasons for Sentinel Druids, Winter was easy. I grew up in the Midwest, and have listened to a fair amount of Garrison Keillor talking about how winter builds character as part of his assorted Lake Wobegon monologues. More than that, there's a remark of Nietsche's: "That which does not kill me makes me stronger." I wanted the basic point to be that winter Sentinels were survivors.
Taking that as a starting point, the chosen weapons were easy: what things could you use to get the food & shelter you would need in the middle of a winter? Spears, axes, slings. For an animal companion, I chose a wolverine as something that is commonly associated with winter or cold-weather environments. Since wolverines have a reputation as being bloodthirsty, the wolverine powers became high-damage powers (although not as powerful as the bear's). The benefits to the druid itself took the form of things to help the druid and his companions survive, either by avoiding damage or by shrugging off effects that were already affecting them.
As before, I got some feedback from people who read the drafts which I took into account. The big change that resulted from this feedback was an additional boost to the damage dice in chosen weapons, and in allowing the sling to be used as an implement. I'm not positive I got the latter part right, and it would probably need some playtesting to determine whether it needs further refining.
The new and revised version, formatted nicely to print, is available here.