Sivalier's Thorns is melee weapon of Sivalier set. Utilize poison damage, it can kill shield zombie at ease.
This weapon utilize poison damage as both main and secondary damage. By using poison damage (which in turn class as magic damage), it can cause damage through shield and cause direct damage.
It raw damage surplus must melee while its Nerve poison can deal DoT, make it ideal weapon fro melee user. Though it poison damage can be offset by Whitestand Elite skill, make it use less against Whitestand zombie.
Though most DoT is offset by Rainbow Shield, it raw damage and its damage bypass physical shield make it capable to kill zombies without it effect. Unless they're Whitestand, of course.