Mysterious letter

The mysterious letter is found during Missing, Presumed Death by searching the bench next to the Temple of Saradomin in Paterdomus. It is used to help Brother Samwell in finding out who killed the monks.

It is presumably directions from Sliske to the wights, who are trying to lure Icthlarin to the area to deliver an invitation to Sliske's ascension to godhood.

Transcript
Your orders:

The gathering is imminent. Once you have everything in place, wait for his arrival. Then deliver the invitation. S