An incarnation of Laserbeak, and condor/cyborgs for the Cosmic Era
Do not meddle in the affairs of wizards... -- Gildor, via J R R Tolkien
The first sign of the Army of the Lost are the legs. Blown off legs, hopping along wearing their military boots. And not long afterwards, the rest of the Army arrives, and the horizon from left to right is filled with the decomposing bodies, many of which carry weapons. Unless you can outrun them or fortify your position, you will soon be joining this army of the Undead.
A young girl with a dirty face and tattered dress stands near the town market offering to sell the PCs freshly cut flowers. They are only a single copper a piece, and smell nice. Perhaps the PCs will be generous with their wealth, or they will not. Great for paranoid parties.