Complex sentence: Native troops were looked down upon and distrusted due to their disloyalty and frequent tendency to aid in native revolts but with the Ptolemaic decline, they gained influence and became common in the military.
Split into simpler sentences: Native troops were looked down upon and distrusted due to their disloyalty and frequent tendency to aid local revolts. However, with the decline of royal power, they gained influence and became common in the military.