Originally Posted by BloodGodAlucard
I apologize in advance if this is a stupid question, but I didn't go for this achievement equivalent in Reach. So I just want to be sure about how it works. For the solo Legendary achievement, do you have to do it a continuous playthrough? (Start to finish?) Or can you change the difficulty and play the levels in any order later on? Because I started the game on Legendary, but I couldn't beat it. So I dropped it down and enjoyed the game. Now I want to go back and finish it for the achievement. Do I have to replay the levels I've already beaten? Or can I just start on the next level I need to complete on Legendary?
The game tracks each difficulty that was completed for each chapter. So yes, you can go back and finish the chapters you missed on legendary and skip the chapters you already completed. You don't have to do it all in one playthrough.