A meal can have no more than two effects, and some meals have none. These effects can be Attack, Defense, Health, or Stamina.
Meal combinations are based on which category the two ingredients belong to. Individual ingredients make no difference in the outcome of the meal, only the category matters: Meat, Vegetable, Seafood, Grain, Oil, Dairy, or Liquor.
Each room at the hotel is only available at certain Hunter Ranks, except the Pawn Room which is always available.
Much thanks to mmPotato for creating their wiki, whose information has been invaluable. Thanks to the many data extracted from the games themselves by 2Tie and Yuzucchi. Thanks to Amaillo for translation info. Thanks to Sammy for some very informative Bowgun meta. Thanks to Lutyrannus for video footage of monsters not listed in the official guide book. And many thanks to the very helpful members of the Monster Hunter Oldschool Discord!
The only social media I really use is Mastodon: https://mstdn.games/@PlatyPete