when can we fight him?Do we need to be at what level?Is he the last quest and battle?Can we use our lvl 80 hencemen to help defeat him?
You duel Malestare after completing all main story line quests in Dragonspyre. He is not the last quest by a long shot. There are now four worlds after Dragonspyre. You can use henchmen of any level in any duel.
You fight Malistaire at the end of DS, people used to be level 45-50 when they faced him, but with WT and other side worlds, you can be a much higher level now before you face him. He used to be the last boss/battle - but since they have added CL, ZF, AV and now AZ (coming soon), he is now kinda in the middle if the quest line. And yes, you can use henchmen.
I don't wanna spoil anything but I have to I can't keep it a secret anymore malistare is the new mysterious person in AZ I am sorry I didn't wanna say it!