An adjective which says it all
An expression in two form
A balance to the  noun
Known as a pair of the  negative and a positive

Everywhere I am found
Where hate is,
My name is love.
Where pain is,
My name is joy.
Where rain is,
My name is sunshine.
Where tear is,
My name is smile.
Where weakness is,
My name is strength.

Power was me
One failed to rule
It belong to a world of two
Where there's black and white

Every story has an intro and a conclusion
Concluding my story
Good is in every bad
Moods control
Sometimes I am best
Sometimes I am worst
I reigned in everything