Rift
originally was the villain who caused the heroes in my
RPG to travel to other alternate Earth's.  He did this
to learn about humanity.  He was a being of immense
power from another dimension.  He would throw them
into dimensions to see how they reacted to the
different situations.  Each Earth had some type of
crisis.  There was an Earth where the Axis had won
the war.  Another Earth had the Mecha taken over
and they had to fight huge robots.  Yet another Earth
Magic Transformed them into magical beings and
England was still in charge.

A QUICK ORIGIN OF Rift

Rift is a single entity in his universe.  He accidentally
learned about Earth due to Photons dimensional
scanners.  He traveled to Earth and made him look
human this caused several dimensions to fracture
Earth.  The Earth was divided by dimensional barriers
and only a few could pass through without being
undone.  The Earth Heroes responded and was able
to repel Rift due to his limited power in his human
form.  With Rift gone Earth Prime was able to
dispersed the dimensional energies.  It was later seen
with Rift in his dimension viewing Earth Prime and
interested in Humanities creativity and individuality.

Rift Powers

Rift can control pretty much everything on subatomic
scale.  There are certain people who can resist his
powers.  These being are either extremely powerful
or have been to other dimensions/times which give
them immunity to his powers.
Rift in Champions Online