I believe you are referring to those event exclusive version for a Taiwan show (I heard only 15pcs available), technically it is the head from the 42 battle damage set, and it is useless unless you have a body to put it on.
Stay away from their MK 42, it is their first pose-able ironman, bad QC, MK 43 has great improvement over the MK 42 even they are more or less the same mold.
Someone gave up his first day VIP Pre-Order for this.
I took the shot right after playing with the demo at Toy Soul 2015 HK exhibition.
It is direct sales from the KA store in HK.
It uses larger size batteries on the HB, very easy to put in, no tools required, just it requires many many of them:) and some of the covers are VERY difficult to open, I have to trim down those locking tab before putting them back....
By just touching it, thigh, upper knee cover, rear leg, feet are mostly die cast, hard to tell precisely coz they are many panels combined.
Lower arms also has die cast armor.