Here's my attempt to use and abuse Possession. I can't guarantee it's
too effective; one of the problems of Possession is that by itself it
can't hurt anyone; you have to use what you get to hurt others.
However, you should be able to pull one or two big guys out,
essentially for free.

Crypt:
Harrod
Sheldon, Lord of the Clog
Selma, the Repugnant
Murat
Nikolaus Vermeulen
Grendel, the Worm Eaten
Aggrippina
Duck
Dimple
KoKo
Carlotta Giovanni
Rafaele Giovanni
Gaspare Giovanni
Rudolpho Giovanni
Mario Giovanni
Cristofero Giovanni

Best: 10, Worst: 36, Average: 5.4

Ugly crypt, but hopefully, that will be to your advantage.

Masters: (14)
2x Recruitment
5x Effective Management
4x Necromancy
2x Minion Tap
1x Secret Library of Alexandria

Actions: (18)
7x Possession
3x Kindred Intelligence
4x Bum's Rush
1x Imperial Decree
3x The Fifth Tradition: Hospitality

Political Actions: (13)
2x Giovanni Acceptance
3x Nosferatu Justicar
1x Praxis Seizure: Venice
2x other Praxis Seizures
5x Might of the Camarilla

Retainers/Equipment: (8)
2x Guiseppe, Gravedigger
1x Hand of Conrad
1x Changeling Skin Mask
4x Soul Gem of Etrius

Action Modifiers: (9)
3x Faceless Night
2x Lost in Crowds
3x Cryptic Rider
1x Soul Stealing

Combat: (28)
4x Undead Strength
4x Torn Signpost
5x Immortal Grapple
5x Disarm
3x Amaranth
2x Ritual of the Bitter Rose
3x Spiritual Intervention
2x Behind You!

Give it a try. It probably needs tweaking, but it will give you a start.
I'm thinking about somehow adding a Storm Sewers or maybe
a couple Destructive Secrets and a Labyrinth.