Complex sentence: He also founded Alexandria Bucephalus on the opposite bank of the river in memory of his much cherished horse, Bucephalus, who carried Alexander through the Indian subcontinent, and died heroically during the Battle of Hydaspes.
Split into simpler sentences: He also founded Alexandria Bucephalus on the opposite bank of the river. Alexander then named one of the two new cities that he founded, Bucephala, in honor of the horse who had brought it to the Indian subcontinent, which had died during the Battle of Hydaspes.