For completing the Ascent of Egypt campaign. 
I must say that I really like the improved history text segments in the campaigns, and the GFX are absolutely beautiful. The game looks stunning, and I have a rusty old GTX 550 Ti that really struggles with a number of recent games; thankfully this is a 2D game and so even with the high quality artwork it still runs nice and smooth.
My only complaint so far is the at times abysmal unit pathfinding, which is something I’d hoped had been improved more than it apparently has been. If there are further updates to this game, that should be the #1 priority (along with the chat box bug, but I haven’t played MP yet so I haven’t experienced it).
Next stop: Glory of Greece!
PS: Hurry up with AoE II: DE.