Shadowheart's Act 2 arc in Baldur's Gate 3 revolves around the Last Light Inn, a refuge for survivors in a shadow cursed land.
The inn is under the protection of a cleric named Isobel, who dies, ending her protection.
Shadowheart's arc centers around the Nightsong, a weapon in the Shadowfell that her god Shar wants her to destroy.
Killing the Nightsong triggers the end of Isobel's protection of the Last Light Inn, causing a shock to the party.
A campaign where the inn never falls has significant ramifications, with some characters lost and others gone for good.
Jaheira, who can be persuaded to join if Isobel dies but fails to survive the battle at the inn if Dame Aylin dies, is inability to recruit.
Jaheira's death also makes it impossible to add Minsc to the party, another character with a significant connection to Jaheira.