Vestments of the Vanguard Guildmaster (5e Equipment)
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Wondrous item, artifact (requires attunement)
Green and gold, the colors of the guild, these vestments are the perfect blend of function and fashion, as to the intended wearer, armor would just be a needless weight that'll slow the wearer down and it saves time when needing to go from meeting with city officials to battle in an instant.
Ancient Vestments. Woven and enchanted to withstand the detriments of time and tribulation, these vestments are passed down from one Guild Master to their heir during the ceremonial promotion of the new Guild Master. When not wearing armor, the wearer's Armor Class becomes 15+Dex Modifier and the wearer never feels discomfort due to non-magical climate effects. If worn beneath armor, the vestments improve the magical armor class bonus of the armor to a maximum of +3. If the armor worn with the vestments is already magical and supplying a +3 AC bonus, the vestments still prevent discomfort due to non-magical climate effects but have no other effects.
Part of the Vanguard's set. The set counts as 1 artifact no matter how many pieces the character obtains. When in possession of any part of this set the character is compelled to be the first into the fray and the last out, unless it is much more beneficial to the party for him to be elsewhere. When the bearer of these Vestments bears at least 5 of the other pieces of this set it gains the benefit of applying physical damage resistance.
Interested Parties. Unfortunately with every artifact comes the interested parties, people who just want it for the sake of it or people who understand what it is or what it can do (How often, who they are and what they do is up to the DM).
Destroying the Vestments. Destruction of the Vestments requires the slaying of all members of the Guild. If no living member of the Guild remains, the Vestments will fade from existence.