Complex sentence: Most games were held on the Onondaga Nation at the Onondaga Nation Arena and the newly-built $6.5 million Onondaga Nation Fieldhouse, although the Iroquois' games versus Canada and the United States were held at War Memorial Arena in Syracuse.
Split into simpler sentences: Most games were held on the Onondaga Nation at the Onondaga Nation Arena and the newly-built $6.5 million Onondaga Nation Fieldhouse. Although the Iroquois' games versus Canada and the United States were held at War Memorial Arena in Syracuse.