Bound Until Death

The Temple of the Divines in Solitude is visited and the Dragonborn attends the public wedding reception of Vittoria Vici and Asgeir Snow-Shod with the intention to kill the bride. A bonus is received if Vittoria is murdered while addressing the crowd.

Entering the temple
Travel to Solitude, then walk over to Temple of Divines. In front of the temple there will be a group of people. In two chairs standing opposite of the temple door are the bride and groom. The Dragonborn can either talk to the bride to start the event, or just wait.

After the Dragonborn has spoken to her, he/she may enter the temple. Take the first stairs on the right, walk upstairs and then out the door which should be on his/her right. The Dragonborn will now end up on top of the roof. If the Dragonborn looks down to his/her right, you can see the crowd he/she was standing in the middle of only a minute ago. Walk towards the gargoyle standing over the balcony.

The Balcony
After about thirty seconds, the bride and groom will get up from their thrones, and enter a door. This door will lead them to the balcony above their place of honor that faces the assembled guests.

Sniper
Gabriella tells the Dragonborn that she has taken the liberty of scouting the area and has left Firiniel's End an enchanted, leveled, elven bow that does 20 frost damage, Elven Arrows, and a potion of true shot on the balcony across from where the bride delivers her speech. The Dragonborn will have a clear shot from this point but there will be a chance of immediate discovery after the shot and pursuit by the guards.

The shot can also be taken from the walkway above the balcony where Firiniel's End was left. The walkway runs all around the courtyard, however the angle and cover options appear best at the furthest corners. Be sure to get into sneak mode, take the shot then back away into the corner (or drink an invisibility potion between release and impact) and stay hidden until the way is clear.

Statue
Speaking with Babette shows that a gargoyle statue above the balcony where Vittoria gives her speech, is loose. Unhinge the statue during her speech to gain a bonus. It is possible to drop the statue on her while standing next to her on the speech platform by crouch hopping. This will make it easier to quickly loot her body but requires high sneak skill/apparel. The wall section / walkway above the bride gives you access to the gargoyle as well. When the bride starts speaking, pushing the loose gargoyle while in sneak, preferably, gives you the best escape route (done right and with the proper sneak skills, no one will even see you), as well as give you the bonus for killing her in the middle of her speech. Note that all the guests and the groom will now be hostile. However, you will not be given a bounty. There is a window between when you hear the crash and when someone calls out where you can fast travel out, making your escape easy.

Frenzy Poison
A way to minimize hostile reaction to your attack (or at least offer a big distraction), is to put a frenzy poison on Asgeir Snow-Shad. Requiring that you have the perk Poisoned for Pickpocketing, Asgeir will attack and kill Vittoria Vici for you. Another method to achieve the same affect is to cast Frenzy on Aesgir, if your Illusion skill level is high enough. After this, the guards will have to fight both him and his parents before they can go after you, and by then you can be out of Solitude, and in the sanctuary.

Plain, Old-Fashioned Murder
If you wish to make a daring escape with the guards hot on your tail, you may simply waltz up to the balcony with the happy newlyweds and plant your knife in her throat, or fire an arrow into her heart from the courtyard filled with spectators. This method does incur the standard thousand gold bounty, just like any other murder, but you will still accomplish your bonus objective, and you may use the thousand gold payment from the contract to pay off your fine. Apparently there will indeed be a bounty when you slay the bride, following up behind them, on the balcony (while sneaking) the bounty is reversed. With a bow, it is easy to snipe the bride while standing on the ground behind the crowd near the door of the temple, next to a small boy. After sniping, immediately turn around and go through the temple doors. The crowd will not follow you and you can fast-travel at your leisure.

Escaping
If you don't escape the area immediately (easily done from the wall above the gargoyle. You can just fast travel out right after pushing the gargoyle), the Argonian Veezara will now appear and tell you that Astrid sent him to assist you. He will take care of the crowd, allowing you to slip away. Being a member of the Thieves Guild can allow for an easy escape as well, because when a guard confronts you you can simply use the thieves guild dialogue option and everyone will 'forget' you ever did anything. You should not attempt to fight the crowd, as killing some of them will give you a bounty. The guards won't assist you nor attack you. Travel back to Astrid to finish the quest.

Achieving the bonus
As long as the bride dies during her speech on the balcony, you will receive your bonus, regardless of the method used. The bonus is simply a large amount of gold. The unique spell named "Spectral Assassin" that summons Lucien Lachance as a temporary follower once per day will be given to you even if the bride isn't killed on the balcony.

Conclusion
After reporting back to Astrid and reporting your success and whichever outcome you achieved, she instructs you to speak to Gabriella, this immediately concludes Bound Until Death and begins Breaching Security automatically.