Water Bolt

The Water Bolt is a magic weapon that auto-fires a slow blue ricocheting water-ball that travels in straight lines, emits a dim light, is unaffected by gravity, and pierces multiple enemies. The projectile can last up to 30 seconds, but will die when it ricochets 5 times or damages 10 enemies. The Water Bolt is uniquely found only in Dungeons, hidden as one of the many books on the shelves within the Dungeon, and cannot be crafted, purchased, or found in Chests.

Its best Modifier is Mythical.

Locating the Book
get a magic mirror and use it to teleport to the book.

Tips

 * It is not explicitly required to defeat Skeletron to obtain a Water Bolt, as platforms with books can spawn above level 0, sometimes even in the room just past the door into the Dungeon. These can be safely retrieved without causing either Dungeon Guardians or unique Dungeon enemies to spawn. As the Water Bolt remains a powerful weapon up until Hardmode, it can be advantageous to check the Dungeon when starting a new world.
 * The durability of the Water Bolt projectile, combined with its ability to ricochet and hit multiple foes, makes it very suitable for fighting groups of enemies, especially in flat valleys and straight passageways. It also has a low enough velocity for it to hit the same enemy more than once even without ricocheting.
 * Because of their long range and ricochet, Water Bolt projectiles can be used to detect Floating Islands by firing upwards and waiting for the projectile to bounce off and return. Their low speed makes this tedious, however.

History
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