G is apparently a very rich man, with a large stake in trans-realm commerce. He is also a collector of antiquities, with special interest in acquiring the Isbari Glaive. While employing thugs, G seems to prefer to put specially-talented individuals in charge of his operations, especially those who’ve managed to maintain some degree of supernal ability post-Change.
The Party destroyed his entire holdings in the town of Gale, and prevented him from learning the Glaive’s location. The party has not seen G, nor do they know what his actual name is – only that they’ve acquired a powerful faceless enemy.