Wachter

What we know

Long-beloved Vallaki family per Baron Vargas Vallakovich (Session 11 @ 01:36:10)
Lady Fiona Wachter is current head; Baron calls her a disappointment (Session 11 @ 01:36:10)
Only open voice of resistance against the Baron in Vallaki per Urwin Martikov and Sylalys (Session 9 @ 02:45:47)
Residence at Wachterhaus on north side of Vallaki (Session 11 @ 00:48:45)
Fiona invited Saturno and allies to dinner seeking alliance against Baron (Session 11 @ 00:44:17)
Wachter family historically in good graces with Zarovich line per Urwin Martikov (Session 12 @ 03:26:32)
Baron tasked party to spy on Fiona for devil-worship evidence (Session 11 @ 01:35:25)
Lady Fiona Wachter allied with party to kill Izek and coup against Baron Vargas Vallakovich (Session 14 @ 02:19:34)
Historical loyalty to Strahd since Lady Lavinia Wachter and traitor Leopold Dilisniya incident (Session 14 @ 01:54:43)
Destroyed village Berez on Luna River cited as cautionary tale (Session 14 @ 01:58:45)

Lady Fiona Wachter — current head; open Baron critic (Session 9 @ 02:45:47)
Lady Lovina Wachter — House Wachter; related to Fiona (Session 9 @ 02:45:47)
Ernst — Fiona's loyal aide and servant (Session 11 @ 00:46:33)
Stella Wachter — Fiona's daughter; catatonic (Session 14 @ 01:27:46)
Mr. Turner — Wachterhaus butler (Session 14 @ 01:23:39)
Frederick Wachter — deceased former heir; Fiona's brother (Session 14 @ 01:40:53)

Ernst delivered sealed dinner invitation to party during Session 11 (Session 11 @ 00:44:17)
Named on envelope in Durst Manor cloak room before party reached Vallaki (Session 1 @ 01:07:28)
Session 14 dinner at Wachterhaus; coup alliance negotiated (Session 14 @ 02:19:34)
Izek killed Session 15; Fiona coup imminent (Session 15 @ 01:03:10)

Unconfirmed: exact relationship between Lady Fiona Wachter and Lady Lovina Wachter (Session 9 @ 02:45:47)
Unconfirmed: whether Fiona serves the devil as Baron alleges—party revealed vampires instead (Session 14 @ 02:12:06)
Unconfirmed: relationship between House Wachter and the Dursts (Session 1 @ 01:07:44)