From Luguvaluim:
Work your way neneennwswnwwsse and kill all the picts (they are agg)
Go s and kill the mini-boss, get key corpse, unlock chest, get all chest
Go nwnneen and ask man help, give him the sword
go ssennnu and throw sword loch (agg picts possible)
go dsswwnn and ask man help, he'll give you the essence of merlin
go to merlin in camelot and give essence merlin, you get the stats and whois
Old verbiage:
Get the Essence of Merlin by throwing the sword of Caledfwlch into the Deep Loch in Pict area. Go back to old man after throwing the sword and ask him 'help' again. Give the Essence to Merlin in Camelot and you will receive +10 mind, -2dex. In lieu of longhouse