Hardest player count
I know its very quest dependent.
But lets say I would like the best chance to beat every quest with only one player count?
My guess would be.
Easiest to hardest:
2 player
3 player
4 player / 1 player (true solo) as the hardest
I might be completey wrong as my main experience is with true solo.
I know that true solo, some quests can be "trolled" or can not unfold their true potential
sometime. I also know that location lock and surge trains can grow out of control the more player you get, BUT.
I think that for a lot of quests demanding to solve all the problems for 1 deck is harder to achieve than for 2 or 3.
There is so much synergy that is missing when you play by yourself.
So many more combos you can try to achieve with a second deck.
Caveat: I'm playing progression style and I'm about half of the game and the potential card pool (Land of shadow right now)