Challenger,
BOTM Gauntlet.
First spoiler (4000BC-1000BC) is
here.
In vanilla/warlords reaching optics is usually done by lightbulbing compass & optics. But it seems that it is not always the best route any more. First the tech order is changed, and alphabet has a higher priority then compass/optics. So using GSs for lightbulbing requires reseraching math & alphabet. The total benefit is only ~1000 beakers. Second the GA costs only one GP.
So I ignored math & alphabet and went straight for Optics. I used my first GS for academy in London and the second one to launch a GA.
London became my top research city (gold, 2 scientists, academy), Kyoto & Osaka helped too working the gems & river cottages. Here is the tech progress:
1100BC - Metal Casting (Oracle)
800BC - Academy built in London, some libraries whipped in other cities. Switch from 0% science to 100% science.
750BC - Iron Working
550BC - Compass
260BC - Machinery
125BC - GA starts
80BC - Optics
25AD - GA ends. It didn't speed up research much, but helped producing troops for the invasion a lot.
While London, Kyoto and Osaka were pulling me to Optics, my other city Oporto, founded in the great production spot near the copper (the only city I founded in this game, except the capital), produced axemen for conquering the aztecs & the inca:
800BC - decalre war on the aztecs.
470BC - aztecs destroyed (Monty had 3 cities, I kept 2).
305BC - declare war on the inca.
230BC - inca destroyed (Capac had two cities, I kept his capital).
I kept producing units after killing Monty & Capac, maybe it delayed Optics by 1-2 turns, but when I got it, I already had some 30 units, mostly axes, but also some swords and crossbows which I could build after grabbing Cuzco's iron. I also had 8 cities under GA producing more units. At first all my coastal cities built carracks, then switched to swords. Inland cities produced swords all the time. Invasion timeline:
80BC - discover Optics
115AD - circumnavigation
145AD - declare war on Persia
220AD - declare war on Korea
250AD - declare war on Maya
295AD - Persia destroyed
430AD - Korea destroyed
475AD - Maya destroyed
490AD - declare war on the Vikings
595AD - Vikings destroyed
610AD - conquest victory