The Powder Toy

I knew that the Death Star was coming, so I placed retro-reflectors on the spot where the laser would hit. The laser reflected off of the reflectors, and struck the Death Star causing it to explode. ...

I turn into a black hole and eat the universe, then I explode becoming a new universe.   The next user was the last thing in left in the universe that I ate.   Offtopic: Why was Bad Luck Br...

Could it also make hydrogen if exposed to water?

WTRV to RIME

However, there was a programming error in the virus, which caused it to crash when it tried to initiate.   The next user is trapped on a planet orbiting a star one second before going supernova.

NBLE to CO2

The element Curium has 96 protons, the same number of posts on the facts game including this post.

Tommig's old mod had liquid hydrogen in it as well. It had some interesting properties to it.

I instantly disintegrate into subatomic particles, only for those exact particles to make me again 13.7 billion years later.   The next user is a blob of antimatter, when the magnetic containm...

Covering the ground in a one pixel thick layer of PLUT, then watching him die of radiation poisoning.