[@Raineh Daze]

Thing is, is that Semiramis's hanging gardens have to be built first, and likely because of what the hanging gardens is there is likely no way gilgamesh would have the mana to manifest the thing as his ties to it would be even looser then say Neba II himself.

I doubt Gilgamesh has the ability to realize the hanging gardens as a NP by himself, he might be able to create a structure like the hanging gardens but without the WMD elements. 

*Although the real hell on earth would be Gilgameshs infinite wealth combined with Semiramis's NP getting stronger the more money is piled into it which results in the strongest hanging gardens ever*

(meanwhile I still think the hanging gardens could be integrated into the citys infrastructure in someway)