You observe Tuatara: Mask of Colaborative Planning (ID: 2877), an army led by Sulcofuron that is attempting to move through Marazion in the Mayan colony, towards Corundum. You pursue the force for several days but the troops outnumber you and are much better armed and equipped. It looks like suicide to engage, so you let them pass.
When you attempt to pass through Marazion in the Mayan colony on your way to Corundum, you are shadowed by scouts from Eyrie Defense Force (ID: 2788), an army led by Lam Trong Quan. They pursue you for several days but do not engage.