Nexon GM admits Mechanic is overpowered.

I think Nexon will most likely release each new class over powered and then nerf it later. It makes sense to do this. It helps push people to create new main characters and in turn drive new nx sales.

Releasing OP new content and nerfing it later is common practice and not just limted to Nexon. For example, about 80% of the most recent heroes in DotA were significantly overpowered in the version that they came out and they have been steadily nerfed since. It's a simple and effective strategy to increase interest in new content.