Core defender

Number one on the list for the strongest units on Command and Conquer. Number two was Mammtoh mk. ii
It is a giant mech taller than a skyscraper that can transform into a shell, then transform again to wreak havoc with its Defender Obelisk Lasers.

GDI Commander- Watch out! Cabal's Core Defender is about to attack our base! Where the hell are those reinforcements??