[At Keith's words, he looks up and—well whaddya know.]

It's a pretty large cluster.

[Swimming right on up to poke one of the smaller half open ones, it immediately closes, but nothing dangerous seems to be happening.]

Big one...big one...big......... Oh. Hah, so it turns out all these small ones are covering the larger one. Give me a sec and I can pry its mouth open.

[Extends his hand out for a sword to appear. Got a big oyster, gotta use a big blade.]

It's facing down, so just be ready in case it falls out. ...Or would it just float since we're underwater?

[Well whatever, he's starting to pry it open!]