Almost all animal life on Earth uses oxygen, due to its powerful ability to oxidize various compounds

While there are many bacteria which use a different electron acceptor, I can find no examples of any more energetic organisms (like animals or protozoa) using such methods

The oxygen-alternatives must be able to function with carbon-water based life, and be stable enough to make up a usable portion of the atmosphere, like oxygen on Earth. It must also be efficient enough for animal-type life

Is there any substance that could fulfill these criteria?