There was a great deal of black potion in the basin. Sirius looked determined to drink it himself.
After all, the Inferi in the water had already been dealt with. A potion that merely made people thirsty was no problem at all. He just wanted to ask Voldemort:
"How much do you have?! I'll drink however much you've got!"
But Su Ming stopped him. Then he pulled an absurdly large black greatsword from his belt pouch. Its blade was studded with glittering silver metal, dazzling like stars in the night sky.
"There's no need to drink it. Voldemort placed warding magic on this stone platform, stipulating that only this little cup can scoop water from it. But this platform isn't like the previous Monolith, which might have been some sort of Space Teleportation portal and therefore couldn't be destroyed. This thing is just sitting here. I only need to give it one hit with a weapon made of anti-magic metal."
As he spoke, Hermione and Sirius saw a silver gleam carve an arc through the air. The flash vanished in an instant. Thanks to the Serum, the girl vaguely caught the attacking motion, but Sirius was still craning his neck, waiting for what came next.
There was nothing else to come. The basin, sliced cleanly in half, slowly tipped along the smooth cross-section of its supporting pillar, crashed to the ground, and rolled a short distance.
Black potion spilled everywhere. The locket hanging from its golden chain also slid to Deathstroke's feet, striking the metal boot with a crisp little clink.
Su Ming bent down, picked up the fake locket, and handed it to Sirius. "Here. Your brother's final letter is inside. Though it's really a taunting letter addressed to Voldemort."
Sirius was still stunned by how fast that sword