Ice Bow

Whatever you load comes out as a frost arrow, and every special property of the ammo is discarded on the way. Frostburn Arrows do not even keep their burn. Load the cheapest thing you own, or the highest raw damage arrow if you are min-maxing, and never feed it Holy or Ichor Arrows.

Since ammo quality is irrelevant here, the Endless Quiver is the right companion the moment you can make one. Infinite arrows, no thought required, nothing given up.

The bow adds its own speed on top of the arrow you loaded, and the frost arrow it produces updates twice per frame, so it flies far faster than the listed number implies. It also means ammo you would never expect, Hellfire Arrows among them, ends up producing the quickest shots. Worth knowing if you are leading targets at long range.

Remix and Zenith seeds swap it with the Snowball Cannon, so it turns up before Hardmode as a much weaker weapon. Do not plan a Hardmode build around it in those worlds.