"New weapons will be added"

[IsoDonk]

This is referring to the text accompanying the new update on the non-JP servers.

Anyone know what these new weapons were?

[Lyrise]

Anything that drops in your mission update. Yamatamisaki, Sanzuhiken, 9 star slicers, etc.

[Carlo210]

Sanzu is nowhere near as cool at shurahiken. The blades look similar to the A rank slicers when shot and they don't look all that unique. However, the sanzuhiken + GRM card combo looks crazy cool.