Sub-aqua ice hockey, also known as underwater ice hockey, is a unique sport that combines two uncommon elements - ice and water. In this game, players dive with scuba gear and play ice hockey using a weighted puck and a stick. The objective of this sport is to score a goal in a submerged net while fighting against the current and limited oxygen supply. Although sub-aqua ice hockey is still a niche sport, there are some synonyms for this game, such as aquatic ice hockey, ice water hockey, and underwater hockey on ice. These terms convey the same principle of playing ice hockey in water, revealing the complexity and challenge of the sport.