Explantion is in the old DBM Army Lists or the more modern DBMM Army Lists.
All DBA Armies are an extract from this much more detailed a.m. Lists.
From DBA Book 2/36 GRAECO-BACTRIAN 250 BC - 130 BC and GRAECO-INDIAN 170 BC - 55 BC
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This list covers the Greek states in Bactria and India from Diodotos's revolt against the Seleucids and establishment of
an independent Bactrian kingdom, until the fall of the last Greek state in India. The Bactrian revolt was subsequent to
the adoption of the thureophoros in the Seleucid army, and the thureophoros appears in Bactrian art. It is likely that
colonist infantry were now similarly armed. A Bactrian army raised by Euthydemos in 208 BC to foil an attempted
Seleucid reconquest consisted entirely of cavalry. The Greek cavalry were probably originally standard Hellenistic
lancers, adopting the bow later in response to enemy horse archers and elephants. A Graeco-Indian coin depicts a rider
in Greek armour with a bow, but also a short spear carried in his quiver. This could have been shortened to fit the
available space, but the method of carriage makes it unlikely to have been long enough to be classified as a lance.
Another cavalryman in Iranian dress is depicted on a silver dish with a cased bow, but using a long lance in both hands
as his primary weapon. This could be one of the Iranian nobility, but has also recently been interpreted both as a
Chionite Hun and as a Sassanid Persian, both of whom occupied Bactria in the 4th-5th centuries AD. A find of
cataphract equipment in a government armoury dates to around 150 BC. More than half the non-allied elements of a
Graeco-Indian army must be of non-allied Indian troops including any elephants. Minima marked * apply only if any
infantry or elephants are used.
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For the full List, go to google and search for "DBA Army List Book 2".
Don´t need to download anythink, just take a look.