"Use a Rope Dart to kill Roberts" is an optional mission objective in Sequence 12 / Memory 02: Royal Misfortune
Walkthrough[edit]
When you are prompted to kill Roberts, head for the nearest lift to the rigging of the Jackdaw. use that to quickly ascend to the heights needed. Wait for the ships to align then cross over to the Royal Fortune. Move to the lower yardarm at Midship on the Fortune. This will give you a good position to take out Roberts without much trouble. Because you need to hang him, be sure that you are targeting him. Otherwise it can take an attempt or two.
