Constructed in 2019 by Sembcorp Marine in Singapore, SSCV Sleipnir is considered the biggest crane ship in the world.
It is owned and operated by Heerema Marine Contractors and has 2 revolving cranes with a lifting capacity of 10,000 tonnes each, totalling 20,000 tonnes when both cranes are operated alongside each other.
The largest crane vessel is like a massive platform that has 8 columns, four on each side and one pontoon per side.
Conventional SSCVs have bigger columns...
https://www.marineinsight.com/know-more/biggest-crane-ship-in-the-world/