Keybrand

Most swords hit the same whether the thing in front of you is untouched or nearly dead. This one does the opposite. The more health a target has already lost, the harder each swing lands, and once something is down to its last sliver you are hitting for roughly double. The ramp is smooth up to that point, so there is no threshold to time. You just notice health bars collapsing at the end rather than draining evenly. It also crits far more often than a normal broadsword does with no help from your gear, which stacks on top of the ramp and makes the finish messier still.

Let go of the attack button partway through a swing and the sword leaves your hand instead of finishing the arc. It flies flat for a moment, drops hard, and plants itself in the first ground it reaches. Press attack again and it comes back to you, cutting through whatever is on the return path. You can recall it mid flight too, so a bad throw costs you almost nothing.

While it sits in the ground it keeps hurting anything that walks into it. Each tick is weaker than a real swing, but the gap between hits is short enough that it chews through anything that lingers. That makes it a fence. Plant it in a doorway, at the bottom of a drop, or on the tile a spawner keeps dumping enemies onto, and go handle something else while it works. Two rules limit that. Only one thrown sword can be embedded at a time, so throwing a second pulls the first one home, and a planted sword returns on its own after a while if you forget about it.

The blade, the flash it makes on contact, and the particles it gives off while embedded all stay fully lit no matter how dark the area is. In an unlit stretch of dungeon a planted sword becomes a landmark you can navigate back to, and the flashes tell you something is standing on it even when you are around a corner.

It comes off the armored skeletons in the Hardmode dungeon, so it lands in your hands around the same time as everything else that place gives up after Plantera. It is at its best in those corridors, grinding through packed groups your last few swings already softened, and at its worst opening on a boss at full health, where you spend most of the fight on the weak end of its own scaling. Its opposite number is the Breaker Blade, which pays out against healthy targets instead. Legendary is the modifier to aim for.

It is a Keyblade. The shape is close to the Kingdom Key that Sora carries through Kingdom Hearts, the bright flare when it connects mimics the hit effects from those games, and the throw and recall are a nod to Strike Raid. Before release it went by Lockblade internally, a name no player ever saw in game. Fittingly, the Breaker Blade points at a Square Enix sword as well.