It works with all nations, but best with nations that get 500 wood when they go to colonial.
U need the card native treaties(gives u a shipment of native warriors from each different allied tribe)
1. Put all settlers at food and start making colonial when u have around 10-13 settlers. U need to get to colonial quick.
2 While u are upgrading to colonial, put like 7 settlers (depending on which nation u are and how many settlers u got) at wood. When u have 250 wood u make a trading post at a native tribe. When u finish your trading post u should have got to colonial and as soon as u get new 250 wood u build another trading post at a different tribe.
3. When the second trading post is ready u should use that card the card native treaties
With french i do this in less than 8 minutes + i have a barrax and can make some musketeers and a very good economy. First card is used on settlers. Second card on 4 settlers and third card will be the native unit card. But u can take second card to get units if u want. But u get the 3 card about the same time ur second trading post is finished
On great plains u recieve 4 land axe warriors, 4 cavarly archers and 2 dog soldiers. I tried this at a map with aztec and maya tribes and got like 6 medicine men and 10 units. Pwnage!! Donīt know what u get from other maps.
Hope this will work for you
Makaveli