Blobfish every time, lions would implode before they reached it’s depth.

Okay, first off, a lion swimming in the ocean? Lions don’t like water. If you’d placed it near a river or some sort of fresh water source, that’d make sense. But you find yourself in the ocean, 20-foot waves, I’m assuming it’s off the coast of South Africa, coming up against a full-grown, 4-pound blobfish with his 20 or 30 friends? You lose that battle. You lose that battle nine times out of ten. And guess what? You’ve wandered into our school of blobfish, and we now have a taste of lion. We’ve talked to ourselves. We’ve communicated. “Lion tastes good. Let’s go get some more lion!" We’ve developed a system to establish a beachhead and aggressively hunt you and your family. And we will corner your pride, your children, your offspring…

What about all the lions vs all the lionfish?

Neither. Both are no show.

Depends on where the battle is taking place. Lions would win on land, blobfish in the ocean.