This past April a massive 80-foot steel kraken was purposefully sunk into the Caribbean Sea on top of a decorated WW2 ship. The former Navy fuel barge and its monstrous passenger were placed underwater in order to jumpstart a new coral ecosystem, while also serving as a cutting-edge education center

Source: An 80-Foot Steel Kraken Will Create an Artificial Coral Reef Near the British Virgin Islands | Colossal