FNS picked it because he is a indian ingame leading god who foks his girlfriend every night.
Xyp9x chose his nickname by just randomly typing shit on his keyboard
Dupreeh picked his because it was his brother's. There are some videos online where some pros explain the madness.
nah I have better things to do
He likes rain
FalleN is because there's a card in the game "Magic" called "Fallen Angel" and he liked it
Nex because he is a fan of wide and long neck
gob b because gob = goblin and b because a friend of his was called B.. something.
Valde, he is called Valdemar
Olofmeister because his neighbor was called something+meister so he copied it and added his first name
BnTeT from TYLOO got his nickname when he play cs 1.6 on Internet Cafe. Someone was using the nick "BonTeT" so he only deleted The "O" and got his nickname.
As for xccurate, the nickname is from the word "Accurate"
only the "A" replaced by "X"
Dust2isBest because he probably thinks Dust2 is the best.
nitr0 from Liquid is because as a kid he really loved to play with liquid nitrogen, so thats why is name is Liquid nitr0(gen)
gla1ve got his nickname from device iirc
there are a few blast pro interviews where pros explain it tbh
and i'm still wondering why people have to have nicknames in esports
even gets easier for caster to say niko than xyp9x