UPDATE
Greetings, grasshoppers.
White Puffles have always been a source of magic and elemental balance. According to Sensei, they've also always been especially powerful in the art of Snow. Also according to Sensei, they're banned from the Water Dojo because one turned it into the Snow Dojo once.
Anyways, given that these fluffy little critters were first spotted around the Dojo, it only makes sense that they be attuned to the magic flowing around the ancient building. Which is why, finally, you can bring your white puffle (including puffle creatures!) across the bridge with you into battle against Tusk's minions!
But what exactly do they do?
For starters, they have the range of a Snow Ninja, and will occasionally attack with you! Of course, puffles are much smaller than penguins, white puffles especially so, so the damage won't be quite as much of course. But every little bit helps in the heat (or perhaps, cold?) of battle!
They also replace your cheesy bonus revive card with their very own Power Card! Instead of restoring you to full health once, this new card will regenerate some health for you each turn, for three turns! Also, it looks pretty snazzy, if I do say so myself.
And finally, of course, they look adorable beside you, which is of course the sole reason I'll be bringing my white puffle, Snowy, with me the next time I trek up to the Snow Dojo!
One more small update, if you're having issues finding a full team of ninjas, after a bit of time you'll be able to go in with just two ninjas, or even solo!
This should help you become a snow ninja much faster, as I know waiting times can be slow occasionally.
So, what are you still doing here?
Go fight some snowmen!