Your costume suggestion
You’ve worn the same long grey robes and pointy grey hat since your long white beard was black, so they might be a bit dusty. Your wizened staff is used more for support than spell-casting.
You've been around for a very long time...a little too long, perhaps. You've done a lot in your life, from mentoring kings, to running schools for, ahem, special children, to all of that silly ring business. Now you're just back to mentoring kings...except your king happens to be dead.
INTRODUCE YOURSELF AT THE START OF THE GAME BY READING THIS
My name is Shazam. I am, er, was advisor to King Toffrey. Darn kids these days never listen. Back in the day we had to walk 3,218 kilometres just to dispose of jewellery. Now it's, “Shazam, pull a rabbit out of your hat,” and, “Shazam, reheat my bath water.” Pfft!