Sunlight

Oxygenate Water, also known as Sunlight, is the spell that Mumbo Jumbo uses in Jolly Roger's Lagoon. Because Jolly Roger's Lagoon is mostly underwater, Banjo and Kazooie's oxygen bar is not strong enough to keep them alive while swimming underwater. Instead, when they give Mumbo a Glowbo, he casts a spell on the entire lagoon by using the sun to "oxygenate" the water, allowing Banjo and Kazooie to explore underwater without needing to return to the surface for air.