Enchanted Sword

It hovers, spins in place for about two seconds, then throws itself at you in a straight line through anything in the way. The lunge starts fast and bleeds speed as it travels, running out entirely after a second or so, so one that misses does not keep going forever. Blocks do not stop it, which means the only real defense is interrupting the wind up. Any damage at all resets it, mid spin or mid lunge, and it never finishes a charge you interrupted.

That reset makes fast, wide melee absurdly good here. An Arkhalis or a Terragrim held down is effectively a wall, because nothing that approaches survives near you long enough to finish a lunge. Melee also reaches it through terrain, which handles the ones winding up inside a block.

Contact carries a decent chance of leaving you Cursed, which locks your items out entirely for a few seconds, and the harder the difficulty the longer it lasts. Against an enemy whose only weakness is being hit, losing the ability to hit is the worst outcome available. If it lands, disengage instead of waiting the timer out where you stand.

It is fussier about ground than most Hallow enemies. It spawns on Pearlstone, Pearlsand, Pink Ice and hallowed grass, and nothing else, so a farm floored with pearlsandstone produces nothing and looks like a bug. It does not require you to be in the Underground Hallow, only that those blocks are there.

It also carries the same activity restrictions as the Chaos Elemental. No town NPC nearby, no safe background wall behind the center of your character, and you must have done something in the last few seconds: moved, jumped, pressed a direction, or used an item that is not a kite. Standing still in an AFK farm fails all of it.

A Shadow Candle suspends every one of those rules and is the clean answer. Without one, hold the attack button down, jump repeatedly with a Frog Leg, or ride a minecart track with hammered bumpers at both ends. Conveyor belts, hoiks and hovering on a mount all fail the movement check, which is why so many farms come back empty.

• Its sprite is Excalibur with a blue glow. Both arrived in the same update, back when no other sword in the game could match Excalibur.
• The enemy predates the item of the same name by a full version, and the item looks nothing like it.
• Every enemy that spins then charges is likely borrowing from the Sword Familiar in Castlevania: Symphony of the Night.