Q:
Costume inter-account character transfer?
A:
If the character is wearing/holding it, yeah, the costume will probably be lost. Just be sure to put it in the bank first, or on another character.
The costumes seem to be account bound, so be sure to put it on the bank.
If a character has anything on it when it’s deleted (wether it’s wearing it or inventory), then the item is deleted with the character and Anet will not replace it as it is considered user error (with the possible one time exception if it’s not such case, like in the case of a hack of your account), but if you put everything of value that is not soulbound to that character in the bank, there should be no problem there.
wrapped up in some crazy ritualist hoo-ha from Cantha.
A real grab bag of ‘you can’t hurt me. They’re called Guardians.
In any MMO, you should have the habit of completely stripping a character before deletion. Bank what you can that isn’t soulbound, sell the rest or salvage it, put the money in the bank (irrelevant in GW2 thanks to the wallet), and exit wearing underwear and a smile.
For clarity, I mean deleting your -own- characters. You’d better not be hacking someone else’s