City of Rats - D&D 5e One Shot

When simultaneous kidnappings of the guard captains son and a notoreous assassin rock Cassomir's Imperial Naval Shipyards, the captain of the guard hires you to join forces with hated assassins to solve the mystery. Can you work together with your enemies to uncover the source of the kidnappings, or will you perish in the shipyards of Cassomir?

This is a one-shot D&D 5e game for 4 level 6 characters. The characters will share a primary objective with each also having a secret, secondary objective. What these objectives are will be discussed with each individual player.
We will use Roll20 for maps, character sheets, and dice rolls. We will use Discord for voice. We will not be using video.
The session time is set in and will take between 3-4 hours to play.
This game WILL be recorded but WILL NOT be made publically available. I am building up a portfolio for my DMing style. If you have further questions about this please feel free to ask.

Character Creation
Level: 6
Ability Scores: Standard Array [15, 14, 13, 12, 10, 8]
Wealth: Class and Background starting equipment and wealth
Magic Items: 10 points to spend on magic items. A rare magic item costs 10 points, an uncommon magic item costs 5 points and a common magic item costs 1 point. All items must be approved.
Legal Content: Races, classes, archetypes, feats, and backgrounds from the following books are legal - Players Handbook, Dungeon Master's Guide, Eberron Rising from the Last War, Explorer's Guide to Wildemount, Guildmasters' Guide to Ravnica, Mordenkainen's Tome of Foes, Mythic Odysseys of Theors, Sword Coast Aventurer's Guide, Tasha's Cauldron of Everything, Volo's Guide to Monsters, Xanathar's Guide to Everything, and Van Richten's Guide to Ravenloft.
Ranger Options: Favoured Enemy - Humans, Elves, Orcs, Beasts, and Undead are all the creature types appearing in this adventure. Natural Explorer - This entire adventure takes place in the Costal city of Cassomir.

Your Character Must ...: Be willing to work with others, even if they are evil. Be willing to work for the guards of a major city.

Setting Details: This is set on Golarion (the setting for Pathfinder) and thus will be using deities from that setting. This game will take place entirely within the city of Cassomir, the second largest settlement in the empire of Taldor and its largest trading port. Taldor itself is a decaying empire whos influence was once so great that most refer to its language as common.