Magic Dagger

Daggers fly dead straight for a good stretch and then drop off, so the practical range is a flat line with a hook on the end. Each throw punches through a few enemies, and the fire rate got high enough that the weapon needed its own hit timer to stop consecutive daggers cancelling one another out. It autofires now, so you hold the button rather than mash it. Water and honey ruin the whole thing: the projectiles slow right down and fall away after a much shorter distance.

Throw straight up at something above you and one dagger can connect twice, once on the way up and once coming back down. Against worms the piercing plus the throw rate does the rest, and The Destroyer in particular melts. Mythical is the modifier to aim for.

The two compete for the same slot. The Shadowflame Knife hits harder per throw, reaches further, carries a debuff and costs no mana. The dagger throws faster and pierces more. In practice the dagger wins on packed groups and on anything immune to Shadowflame, the knife wins on a single target at range, and neither is a bad answer if the Mimic only gave you one of them.

Remix seeds swap this with the Wand of Sparking. It stops being a Mimic drop and turns up in ordinary chests or on the Skeleton Merchant during the third quarter moon, so you can be throwing daggers within minutes of spawning. It is scaled right down to suit that slot, so treat it there as a starter magic weapon and not as the Hardmode one described above.

The tooltip implies a single enchanted blade that flies home before the next throw. Nothing about the weapon behaves that way. Several can be in the air at once and none of them visibly come back.