What is the RNG application?

Loki can speak for himself but I believe he's referring to the generator you use for items that assigns stats to them? I think you've told us before that the game automatically gives certain items a certain amount of stats based on the item level. This obviously makes designing a vast amount of items a lot easier but creates an issue when properly determining what "good" stats are. For example, the new vexar mage cape has heal on hit as the "extra" prop for being higher ilevel than an ordinary vexar cape but heal on hit is virtually useless when you compare it to the vexar warrior cape that is granted another hp steal. There are these type of things across a bunch of items in the game