I was snorkeling last week in Curacao and Aruba, and 2 different times when poking my head under a big rock, I was face to face with a porcupine puffer that was substantially bigger than a basketball, when not puffed up.
I had no idea they got that big. Most of my hand could probably fit in its mouth.
I tried to get some pics with a cheap underwater disposable camera, they probably won't come out, but we'll see.
I thought about trying to make it puff up, but couldn't find a 20' pole.