Gwen again :P

just noticed she said something about "old mack and his bull"... anyone know where this old mack is?

Old Mack is the guy you get the devourer egg for in pre-searing. It hatches and ends up as a devourer named Joe which you see quite often associated with side-quests in post-searing. He only raises pets to defend his land, his first one was the bull and "you" killed it in order to turn into a mesmer (Althea's Quest). If you turn into a mesmer, zone back in and out of ascalon then you'll see old mack yelling at Althea, he'll then start to walk away... slowly...