@Sitalkas : A. Ariana is a key city, 2 luxury ressources.
My bactrian strategy :
- Settle Bactra, spread hellenism. Hire the horse archer mercenary. All troops + settler go to Samarqand. Revolution for all civics you can switch. Research Horticulture. Build archer in Baktra.
- Conquer Samarqand, you may lose a lot of troops. Try to keep at least 1 heratoi and 2 archers. Build wall, then archer in Baktra.
- Settle Osh in Ferghana, spread buddhism. Alexandria Mariaga flips to you, build wall then archer. There are always a Spearman and a Heavy Spearman. This Heavy Spearman has to XP and be protected at any cost !
- Conquer Alexandria Ariana. There are a Heavy Spearman and a Spearman in the city. Build a wall, then gold.
- Watch out every turns for mercenaries and hire them. Try to maintain the research in positive.
- Bring your troops and conquer Taxila. Build palace. Now, your Heavy Spearman should have Pillage 1 and Pillage 2. Dont lose it ! For Taxila, build improvement then sacrifice all your slaves to hurry the production of Palace, then Mint.
- Finish the conquest of India ! Be patient : soften the units in the city with your Heavy Spearman, he gets nice XP. You will get soon a General for him ! He's the backbone of your glorious odissey in India.
Important :
- It is mandatory to capture the holy cities in India, nice gold boost. Bring the archers you built to defend it. You'll get a GP to launch a Golden Age later.
- Don't forget to have a heratoi + 1-2 archers in each Ferghana, Bactria, Margiana, Arachosia and Sogdiana city to kill the horse barbarians. Defend these city better around 100BC, before the saka spawn. You'll need 4 archers, 2 heratoi at least in every city (with walls) in N-W India to defend.
- Technology : Horticulture + Siege engine + Markmanship. That's all you need ; your are a warmonger civ, which switch to a defensive civ later. Trade all technologies you can but NEVER give military tech to close civs.
- Protect your 2 workers. Use slaves to help them build improvement, then sacrifice them to hurry production.
Good luck

By the way, I failed the 3rd UVH because I didn't save enough gold, but it's doable. You can't hold the Kushans except if you have Marksmen... but it's hard. Really hard.
@srpt : I had lot of fun. I feel like
Menander when I conquer India ! Strabo said of him that he
"conquered more tribes than Alexander the Great."
But in my opinion there is a problem in the mod : conquer foreign core doesn't hurt your stability enough.
About the dynamic names, we can't guess how they called themselves. Probably it was "Kingdom of Demetrius", "Kingdom of Menander"... and "greeks" for their people ? I agree Sitalkas with "Indo-greek kingdom", but need Gandhara as core imo when the capital is in Taxila (and maybe lose Margiana/Bactria as core).