The Rune Wizard is a rare Hardmode Caster type enemy that is found in the lower Cavern layer. Upon spawning it will proceed to fire magical projectiles at the player that penetrate terrain, similar to that of the Fire Imp's. However, unlike the Fire Imp's projectiles, the Rune Wizard's cannot be deflected with weapons. Rune Wizards will teleport to a new location after firing 8 projectiles in random intervals, or after receiving damage. It will always drop the Rune Hat and Rune Robe upon death.
It is one of the few enemies that can be detected by the Lifeform Analyzer.
- Rune Wizards can only spawn below a certain depth level. This level is below -795 on small worlds, -1323 on medium worlds, or -1718 on large worlds.
- Rune Wizards are immune to the Poisoned and Venom debuffs.
- The Rune Wizard can be very dangerous to players with weak Hardmode items, especially if it spawns in an unreachable place.
- The Rune Wizard seems to be like a Hardmode version of Tim. The vanity items dropped closely resemble the same items dropped by Tim. The two also have similar attack patterns and drop unique items only obtainable by defeating them.
- When it is ready to shoot, it is invisible and has green and yellow flames in its place. When it gets hit, its flames disappear and becomes visible and will teleport and becomes ready to fire projectiles when it stops taking damage.
- The Rune Wizard inflicts extreme contact damage, enough to kill most players in 3 hits. However, its spells do far less damage, at around 50 with endgame gear.
- An easy way to fight this foe is to continually attack him. This will essentially paralyze him, preventing his attacks and teleportation. Lighting him on fire can be a very effective way to fight him.
- The Rune Wizard inflicts the second most contact damage of all enemies, and the third most damage in the game. Its contact damage is as much damage as the Pirate Captain's cannonballs, Skeleton Sniper's sniper bullets and Clown bombs, third to the Martian Saucer's death ray (berserk) and the Dungeon Guardian, but as it doesn't attempt to touch players, this isn't very important.
- Due to the extreme contact damage, it is easiest to fight the Rune Wizard using ranged weapons. However, due to the narrow caves where it spawns, this can be difficult.
- The Piranha Gun is very effective against the Rune Wizard since the piranha follows teleports.
- The Megashark is extremely effective at keeping the Rune Wizard paralyzed due to their high rate of fire.
- An effective but extremely dangerous way to kill the Rune Wizard is to wear full Turtle Armor and run into the Rune Wizard 2-3 times until it dies, but a player may need to consume a Greater Healing Potion or Super Healing Potion.