I am made of stabilized positronium. Because positronium atoms do not contain a nucleus, the neutrons have nothing to bond with, so they simply pass through without harm.

The next user has molten tungsten poured on your head, resulting in near-instant vaporization.

I wake up.

The next user divides by 0.

1/0= infinity. There. I did it. Nothing happens.

The next user is hit by an antimatter missile.

As annoying as it may be, I am. The. Troll.

The next user is hated by every single person on Earth.

I am dictator of everyone. Everyone hates me, but can't do anything about it.

The next user has a troll face on their face forever.

...U mad bro?

The next user is in the center of a neutron star.

I may not have anything material, but luckily (Due to an accident at birth) I have the ability to teleport. I teleport above the next victim, and drop large tungsten rods on top of their head, killing them via orbital bombardment.