With the first anniversary of Monster Hunter World coming up, Capcom have done a lengthy announcement for 2019's content pipeline and let's dig into the biggest announcement with the G Rank/Ultimate sized expansion with Monster Hunter World: Iceborne that is stated to feature new quest ranks, locales, monsters, moves and gear in addition to a full narrative experience that continues on from the ending of Monster Hunter: World. More details will come in the Spring update in 2019, all of these details are for console. PC has nothing confirmed yet.
Witcher 3 Collaboration
Professional Monster Hunter Geralt of Rivia joins the Monster Hunter World with his very own special collaboration. This is set to feature RPG mechanics and the voice actors for Geralt have also contributed newly recorded dialogue to further enhance this collaboration. No other details have been given, expected to arrive early 2019.
Arch Tempered Nergigante and Kulve Taroth
Nergigante is only given a release schedule of Spring, no other details have been given. Kulve Taroth is getting a reworked though, whilst her mechanics are still going to be the same. She now has a new mode which is called "Fury" which will yield new more powerful rewards and her Gamma armour set. As well as this, new weapons are being added to her pool. Her new mode will come onto console on 20th December until 3rd January.
Not much to say other than it's like any other festival which will contain every single released event quest returning, special meal in the gathering hub, and new content to fit with the event. A new event quest is expected to drop and anniversary quests. This is expected to come January 2019.
And to round out the update, players on console will be able to experience the first 3 Ranks of Monster Hunter World in a trial. This will allow you play with players with the full game and have a save transfer into the full game. This will be made available on 12th December through to 17th December. More details can found on their website (link) and to note, this is limited to console.