1 . You can find datamined sortie rewards on some sources e . g . Voidglitch 2 . I personally say no it is not difficult , but in some occasions with certain modifiers you may find it difficult yes . Especially if you only did SednaPluto levels at max . 3 . I solo or duo with my best buddy all my sorties , except interceptions for obvious reasons . But I got all framesweapons , so you will need to go public from time to time if you don ' t have a decent sniper , for example . Sorties in general are 3 highlvl come at me endless players missions with certain modifiers , check the wiki for these . New set of 3 missions every day . Rewarding 20 k , 30 k and 50 k credits and one of the sortie rewards after completing all three of them . Just some daily challenge , you might want to do Used to reward certain VandalWraith weapons and Nezha but these days are gone since TWW .