Halo: The Master Chief Collection - Halo 2 - My Work is Done - Halo 2: Collect the Librarian toy in Uprising. This achievement is fairly easy to unlock.
On the mission Uprising (make sure you have the sputnik skull on), when you exit the building you need jump up the rocks on the left and turn it to the classic graphics.
Grenade jump up the ledge or use a brute shot to launch you up. Turn to the right and run along till you can drop down to you left and then again on a small path that you will follow till you see a jackal sniper.
Jump up to the right where the sniper was and continue walking up the hill. Keep walking till you get to a point where you can drop down. Walk till you see some skinny trees where you get to another ledge and walk all the way down it.
Continue straight till you reach the end where the toy is located.
Run over and it up and your achievement should pop! Enjoy!