CIMC Gretha，Semi Submersible Crane& Accommodation Vessel, Main deck crane 2 x 1800Tons. As the owner Ocean Challenger got involved in the later stage supervision management for the vessel in March 2012. The sea trial began in 14th August 2012. Yantai CIMC Raffles delivered it to OC on 18th December 2012. After that OC assisted shipyard to complete the modification as requirements. CIMC Gretha delivered on 25th November 2013 at last and reached in Brazil on 9th March 2014. 18th April 2014, it succeeded to pass the inspection by Petro Bras and started to work in Brazilian water.