The Order of the Holy Seal is an order of warriors, motivated by anger, rage and a thirst for revenge (though they're not so keen on revealing what they want revenge for, at least to non-members.)
Scarlett can discuss joining the Order with Rangar at the guild's headquarters in the Outer City. Rangar offers free training in some Physical Skills there as well (he's especially keen on teaching blocking.) (Scarlett will have a letter from Yngvar, a member of the Order, to deliver to Rangar as part of the A Letter to Venice quest, anyway.)
This is the Guild Benedict aspired to join.
The guild reveres their order's founder, St. Anthony.
Inside the guildhall, members may find a bed to rest in.
Rangar also offers additional training inside the guildhall. (Scarlett can learn all those additional skills even if she joins a different guild, but for some she will need to use different trainers ( i.e., teachers).)
Scarlett will need to complete a test before she's admitted to the Order of the Holy Seal:
- The Order of the Holy Seal Retrieve the Shield of St. Anthony from a tomb in the Outer City Catacombs.
Scarlett may request additional quests from Rangar to increase her experience or boost her reputation:
- The Sword of St. Anthony Retrieve the sword of St. Anthony from a tomb in the Inner City Catacombs.
- The Helmet of St. Anthony Retrieve the helm of St. Anthony from a locked room in the Arsenal District.
- The Harness of St. Anthony Retrieve the harness of St. Anthony from a far-away land.
The four quests above are only available if Scarlett joins the Order of the Holy Seal. (In fact, if Scarlett joins a different guild, she may encounter a few locked gates requiring a special key that will keep her from entering the shrines to St. Anthony.)