What is a troll ?

People talk about "Drop da bomb", new troll by deadmau5
(Honestly this guy is a genius !!)
I did one myself 3 years ago !
In 2011 I already felt that drops in electronic music were progressively losing their melodies and creativity.
And I illustrated it by myself by going from this :
https://yakanofficial.bandcamp.com/track/shenzhen-nights-original-mix

To this :
https://yakanofficial.bandcamp.com/track/shenzhen-nights-clubbing-vision