I've never seen permanent pieces before, even in a fan faction! It's such a simple but unique premise that I'm really glad you've come up with an implemented here
I really like the wording of temporary warrior in public support. Not only could you technically ignore a hit, but they would contribute to your own rolled hits as well. Neat! And fits well in the story you're telling.
Your pieces being on the edge of clearing is also a really cool use of design space that would be interesting to watch pan out in an actual game.
One concern is that we're encouraged to craft to find those last few points for the win, like the otters! But if crafting doesn't pan out, the otters have the option to battle for those last few points in the endgame. Just a little difficult for these lil buddies to do the same. Though that's definitely something to see in playtesting rather than just looking at a board and predicting this situation to happen :P
Really cool faction with a really sweet environmental premise that I relay love sooo much. You've also left yourself space for some cool artwork once you've got your animals chosen too. Fantastic stuff!