The Gloom: Unwelcome Guests expansion adds one player and 55 cards to the game. Here is a description of the expansion from the publisher:
In the Gloom card game, you make your eccentric family of misfits suffer the greatest tragedies possible before helping them pass on to the well-deserved respite of death. Just mix the 55 transparent cards in this new set together with your copy of Gloom to add morbid new Modifiers, Events, and Untimely Deaths, and a new family – the malodorous Malone mob – including The Broken Arms Hotel as a Residence card to use with the Unhappy Homes expansion. When Boils Malone brought his family overseas to “get away from the heat,” he wasn’t expecting quite so much rain!