Paladin

The Paladin is a Hardmode enemy who spawns in the Dungeon and throws hammers that go through walls. He can drop the Paladin's Shield, Paladin's Hammer or Armor Polish. The Paladin also possesses the capability of randomly teleporting without effects to back it up in the event it gets stuck. He walks very slowly, but no one should ever underestimate the power of his hammer. (Note: As of 1.2.0.3, hardmode dungeon enemies now only spawn when Plantera is defeated in the same world.)

They are immune to the Poisoned and Venom debuffs and only spawn in dungeons with a Brick Wall.

Tips

 * Be very careful when getting in his line of sight. He won't ordinarily throw his hammer at you if you're out of sight but it can be shown that he has the capability of doing so. He may also choose to throw his hammer if you jump while you are within melee range.
 * You can interrupt his attacks and prevent him throwing his hammer just by constantly firing at him. His normal melee is much weaker than his hammer throw, so it's better off taking a risk and running through him if necessary.
 * The Chlorophyte Partisan can handle him from behind walls thanks to the smoke it emits right as it starts retracting. Use this to easily defeat him, but you'll have to constantly punish him. Keep your guard up for Necromancers as no doubt you may get swarmed if you don't pay attention.
 * The Death Sickle is highly effective at defeating a Paladin in under a minute thanks to high DPS and DOT, and the fact you can hit him on the other side of a wall/floor/ceiling.
 * The paladin has a bad habit of spamming hammers if the player is at a lower elevation than him, be it one block or forty. Attempt to attack down at him, and don't fight him in hallways, as it leaves no room to dodge his hammers.
 * If you have the Shadowbeam Staff, you can stay out of his sight and attack him indirectly by bouncing the beam on walls.
 * Using Shroomite armor will result in the Paladin constantly throwing it's hammer at you, even in melee range.
 * Standing above him and using a Nimbus Rod, you no longer have to worry about the hammers. you DO have to worry about him moving out of place and tossing a hammer while you attempt to deal with other mobs.  highly suggest spectre armor for this situation.
 * You can use a "hit and run" strategy using Magnet Sphere and highly suggested, Spectre armor. This will cause you to be out of range for his hammers and heal you up in case you take damage from a few of them while using the Sphere.