What are the limits on what a Warcraft OC can "bring into" the game (or really, have access to in some way or another)? Items in their absurdly extensive inventory? Bank contents, void storage contents? Mount summons? Transmog gear? Companion pets? Relatedly, do any of these Warcraft conceits, or various others like transmogrifiers, mailboxes, flight masters, etc. exist in the setting?