Destiny: 10 Things You Must Do Before Rise Of Iron
6. Complete Flawless Raider
Back in Year One, this achievement/trophy seemed virtually impossible. Even now going for this seems incredibly overwhelming. However, it is way easier to do now than it was before. You're now a lot stronger, making it easier to go through the old missions and raids with little challenge.
Crota's End was, and still is, the easiest raid. It required the smallest amount of teamwork and had plenty of ways to cheese through it. It's pretty much a cake walk at this point, and is your best bet at going flawless.
The hardest part of going flawless will of course just be the communication between fireteam members, and the easiest way to do it is having the smallest group possible.
If you can do Crota's End solo without dying, then go ahead and do just that - if not, you should be able to do it with two or three people. Practice makes perfect, and don't be surprised if it takes more than one run to get the deed done.
Just be careful, go slow and get your achievement/trophy.