Staying alive solo during the last boss is hard enough as it is with all the adds and moths. I think having to do 10+ rotations of damage to kill the final boss makes it just a little bit too difficult for the solo player to do a perfect run for that long. I love this game and have just started to try to challenge myself by doing the hardest things. I just tried a run for four hours got to the final boss and my last two hours were just trying to beat the witch. I was using bonk solar titan which has one of the highest survivability with arbalest to destroy her shield in one tap. I was also using a trace rifle for moths she spawns and a linear fusion rifle for damage. It’s a load out I found on YouTube to beat this boss solo. It works well but I found it difficult to keep the rhythm going for at least a 45 minute boss fight after already going through the entire dungeon. I was just fatigued and had to get off the game. This reset my progress on the solo triumph which has the requirement of beating the entire dungeon solo without leaving the activity. It sucks to have wasted so much time but I could just not keep going as I do not have the time. I think a good fix if the boss health isn’t lowered is changing the triumph to where you can leave the activity and come back another time. I don’t think I’m the only one who needs mental breaks from this game because although I love it it’s just frustrating when you mess up one time and die to erase the 30 minutes of progress you just spent on the boss’s health.