Sea Crates

 (also know as Block It Out) is a recurring challenge in Survivor.

Rules
A pair of castaways from each tribe would swim out into the ocean to retrieve one of four crates with a different color on each face of a crate. Between the beach and crates would be a "battle zone" marked off by four flags. Within this zone, an opposing tribe member would try to prevent the two castaways from crossing the zone and reaching the crate. Once the two castaways crossed the zone, they would bring a crate back to the beach, and a second pair of castaways would go out to retrieve another crate. Once all four crates were retrieved, the crates would need to be stacked so that one color didn't show more than once on each column. The first tribe to complete the puzzle would win.

In, instead of retrieve the crates from the sea, the castaways would solve a puzzle to obtain a hatchet and cut a rope which would drop a bag with the colored cubes.

History
In, Galu never lost their lead and won their third consecutive immunity and comfort items.

In, even though Edna received verbal assistance from the others castaways, Ozzy was able to continue his win streak at the duels.

The challenge will re-appear in as the duel between Laura M., Tina and Vytas.