HOT "games" problems
They are all solo adventures although a few of them can be influenced by other players (either positively or negatively). Awhile back I wrote a post of my recommendations of which adventures to run for players who just want the minimum number of mastery points from them that they need to max their mastery levels.
https://forum-en.gw2archive.eu/forum/game/hot/Navigating-the-Adventure-MPs