you can do 99% of the game solo because ill be playing it solo most of the time.
the one thing that wont be done this year solo is bosses, i would need a high level char with really good kit to solo the bosses now they have phase mechanics and instant wipe mechanics if not killed in a certain time (some bosses have this mechanic not all of them)
as an example, WT is a 3 phase boss, 1st phase is basic attacks/rage, 2nd phase introduces a ranged attack (almost all bosses have some form of range attack to stop wizards just tbolting over a wall, except for a few that you will have to work out) WT's 2nd phase will also occassionally target a random class in range, so the more classes you have in your group the easier it will be to mitigate its damage spread amoungst you all rather than 1 or 2 people. the 3rd phase WT summons an ultimate attack that will instantly kill anyone in range (regardless of being in the group or not) the idea beaing that you are forced to kill it in time, if you dont it insta kills then resets to phase 1, so if your saved by saving grace or revival ring you still have to start from scratch.
i wasnt going to give AI away but there not that technical tbh.
EDIT: once ive got a dedi purchased ill do a full advert as ill need the IP for the advert.