I’d recommend Borderlands 2. If you want to be a nigh unkillable psycho bad ass, try Krieg. Do absurd melee damage and hulk out, which refills your health. In that mode it refills your health again every time you kill an enemy. If you activated near death the ability timer resets so you can use it again just as soon as it ends Once you get some abilities and artifacts for synergy and to upgrade the melee damage you’ll be one shotting a lot of tough enemies. Even if you’re fighting a boss monster that you have no hope of beating, if they spawn smaller minions throughout the fight you can space out killing them to keep yourself alive as long as possible. you can play solo be practically invincible in most situations.