I don't know much about the region, but it seems Tasmania should at least be expanded by 1 tile west to make it equivalent to the current map.No, I have never touched that part of the map [Tasmania], suggestions welcome.
There goes my UP idea for Teotihuacan...Obsidian exists in Mesoamerica, Ethiopia, New Guinea and New Zealand. The intent is to make this another prerequisite for the earliest tier of military units (i.e. Spearman and Swordsman) but not later units like Heavy Swordsman and Crossbowman. This way deliberately metal deprived civilisations can still have a greater unit variety. Not sure what to do with the Inca in that regard. I know that other obsidian deposits exist but I'd like to limit its placement for this particular purpose. If there is another source that saw significant historical use let me know.
The Inca get copper, so it's not much of a problem, is it? But Wikipedia says that "in Chile obsidian tools from Chaitén Volcano have been found as far away as in Chan-Chan 400 km (250 mi) north of the volcano and also in sites 400 km south of it" (note: not the same Chan-Chan) so there could be some obsidian in Chile.
I like the Rare Earth, it's very unexpected. What tech will reveal it?