"First book in the chronalogically adventurous Drenai series (I'd just read them in publication order). Technically Heroic Fantasy. A prolific author till the end, the Drenai is the tip of the iceberg"
"The first omnibus of the (quite an old series now considering that the omnibuses themselves are very new) Monarchies of God series. His stand-alone "The Ten Thousand" is also military fantasy."
"Redwall is another chronalogically adventurous series. Its huge. The later books veer away from military fantasy but most of it delivers the action in spades."