the stores in esthar?
Nope...
(SPOILER)the exchange part of the riddle, 'satisfy a desire, in exchange one of the best' is literal.
card queen? someone else take it if im right
chocobo?
The 1st edition of Weapons Monthly? (The one that gets the ultimate weapons, not the lvl 2 ones.)
Oh I forgot about this :P
Nope and no.
Though Choco Boy is getting warm.
Not sure if it's been guessed yet, Timber Maniacs?
Girl Next Door?
Found around a center of information, - Timber Maniacs
A red herring amongst the rest, - Found in one of the Timber Maniacs piles
Favoured by those with primal imagination, - Zone ;}
Satisfy a desire, in exchange, one of the best - You get the Shiva card in exchange
I'll leave it open for grabs for now, and anyone who wants to can have a go at making a riddle. If nobody takes it I'll try and think something up.
I will serve you only if you aren't
taking down the green instead.
In the giant pillar, your enemy
will 'reverse' me, but don't be afraid.
For another will serve you now,
even though he's maybe bad.
Odin! When you're in Centra Ruins, you have to choose between getting him or "the green", i.e. Tonberry King (lines 1 and 2). Seifer "reverses" Odin's attack which defeats him (line 3 and 4). He's replaced by Gilgamesh (line 5 and 6).