"Now, one last thing. I will need an heirloom, such as your staff, from each person who you wish to be granted access. In order for the spell to recognize each heirloom, I need to bind the barrier to this heirloom. This brings with it a few minor complications. First, should anything happen to the heirloom, such as it breaking, the barrier will cease to function correctly, and once more anyone will be able to pass." Vyraena explained, pausing for a moment for Lord Beirne to be able to process the information.
"Second, if the staff is stolen, the barrier will not recognize that the heirloom is not in possession of its proper owner, and will allow whoever has it to pass. This means that if someone is careless with their heirloom, the barrier may as well never have been constructed in the first place."