"Now brush the back teeth on the left side ... the final Pokémon Go–style swipe to toss a Poké Ball at the mouth monster. I tossed the ball, certain that I’d get some reward for my struggle ...

At first glance, the world’s second largest fish might seem menacing: Its gaping mouth has six rows of teeth in its upper ... to “great-nosed sea monster” in Greek. In reality, these placid ...