Sometimes it gets confusing, wondering when to use Warfare stats and when to use Strength stats for combat. This is the unofficial wiz-word from on high:
Strength is the attribute that governs combats where both parties are unarmed or (with some exceptions) have natural weaponry, as well as random things with grapping. Warfare is the attribute that governs combats where one or more parties is waving a weapon around, plus abstract combats (chess, army deployment, etc). Shapeshifters may (if they think it's reasonable) always have 'arms' (a tail stinger, honking big claws, whatever) and so almost always fight on Warfare (if you're actually grappled, it goes to Strength. Natural weaponry is generally Strength (it's always Strength for people without Shapeshifting).
Hope this helps. Remember, if in doubt, negotiate OOC with the other player(s) involved. We're here to have fun and interesting Roleplay.