Frost Staff

It behaves like a gem staff with an ice theme. The bolt stops at walls, clips through one enemy and keeps going, and there is nothing clever about the aiming. What earns it a slot is the chill it leaves behind, since that keeps ticking while you reposition and stacks up well on anything with a deep health pool.

Both of the things that drop it live in the cold half of the world and neither is common, so most of these turn up by accident during a trip through the snow rather than at the end of a deliberate farm. That suits what it is: a serviceable stopgap for the first stretch after the walls go up, not something worth chasing.