Following the extrapolation idea I mentioned, here now would be the description of warfare in the prehispanic Philippines, as described in WH Scott's excellent book,
Barangay.
Once again, this is not 13th century. But I think that from 13th century till the early 1500s when the Spaniards first started documenting what they saw, things may not have changed much as far as weapons design is concerned (that's just a hunch though).
There will be three locales described -- warfare in the Visayas (central Philippines), in Bikolandia (southmost portion of Luzon, and Luzon would be in northern Philippines), and in Tagalog region (present day Manila and surrounding areas).
[Note: I'll post the pages one at a time. If I post them in one 'go', the sequence gets jumbled.]