JustinCase
the magical equivalent to the number zero
If you raise the level to 6, one could also play a Storm Herald barbarian ("Storm Soul: Sea: You gain resistance to lightning damage, and you can breathe underwater. You also gain a swimming speed of 30 feet."). Just to be complete.
I think a sea elf monk or moon druid would be nice to play, or perhaps a lizardfolk warlock. There's just something very thematic about a deep diving lizardfolk that with that invocation doesn't need to hold its breath (for up to half an hour). Perhaps struck a deal with an ancient (sea) hag and, due to its in-the-moment attitude, just goes about its way and worries about any commands when they happen.
Then again, wild shaping into something fishy seems like a good fit, too.
I think a sea elf monk or moon druid would be nice to play, or perhaps a lizardfolk warlock. There's just something very thematic about a deep diving lizardfolk that with that invocation doesn't need to hold its breath (for up to half an hour). Perhaps struck a deal with an ancient (sea) hag and, due to its in-the-moment attitude, just goes about its way and worries about any commands when they happen.
Then again, wild shaping into something fishy seems like a good fit, too.