Well, my buddy and I co-op and we just reached Rex, but his minions are dead. Before we fight him, we wanted to do everything else to get as high of a level as possible. I think we have... Rex is the only thing left, but there are some unresolved things:
1. There is supposedly a grave-mound of an Orc that contains a full set of really nice armor. We couldn't locate that mound... Do we need to use perception potions to see it near-by?
2. There are quite a few Level 20 chests around the Church (from graves) and keys are nowhere to be found!!! We dug up every one of those mounds to make sure!
3. Where are the cats that want to get married?
4. There is a house close to Cyseal Villa teleporter that has rooms filled with traps. It also has a giant Chimney where you can Boost your armor. We can't get through these rooms, the one with electric cloud. In fact, we've yet to figure out how to get rid of these electric clouds...
5. Is Nick's Head somewhere in Cyseal?
6. There is a Well that teleports us to a snowy place. Its a quest about saving some brother. Our Journal now says we found a way to save him, but the doors in that place are closed. How do we get by?
7. Are there some secret merchants where we can sell ALL of our loot? Merchants run out of money and just like in most games, there really is no need to buy anything from them, other than repair... I always thought that this part sucked in all RPG's except Diablo games, where merchant items can be incredibly good AFAIK.
Finally, should we wait to fight Braccus until we're level 10+ or so? He seems incredibly hard. So far it seems there are no more big quests left in Cyseal to level up!