id, it might be diamond...he has around 2kk atm...
But usualy people sell the tc so there is nobody that has big ammounts from what i know off.
Killer3366 had around 14kk in he's dueling prime
Firebolty hoarded around 15kk at some point
Shockey was dueling like 20kk/month when he was dueling a lot
I just sell them whenever i can
most i hoarded was 4kk
last 2 weeks i sold 1 mili and lost aoround 1 mili

people just don;t keep tc like they used to, they just sell it from what i noticed...