Fog

Any general tips for dealing with fog of war? I always think I'm amassing a big enough hidden army, only to learn that others have done a MUCH better job who then steamroll me.

Fog is hard, and different situations require different things.

But when you think you are doing well, go scout something, look at how others are doing and how the map looks like. Information is important!

There are two possibilities:
1. You are really well, in that case losing a couple of troops is not a big deal.
2. Others are doing much better, in this case you have lost some valuable troops, but at least you know that there's a danger and you can do something about it

So yea, no reason not to spy (if you are some sort of state of being alive that is).

Go for bonus armies, but don't let anyone know exactly how much bonus you have. When you put troops on the map, pretend you have 3 troops, and put the rest elsewhere. Whenever you put troops on the map, or attack, be aware of who could be watching, try to only let each player know about a subset of your troops, they just know about different subsets.

Try to deny your opponents information, for example, if you are clearing out a region, be careful what order you take them out in, take out the one who is the biggest threat, or who might be able to see you win the region, that way you can pretend you will take the region in 2 turns, but you take it in 1 for example.

Don't let other players know where all the weak players territories are, try to keep them in some hidden location so that only you can defeat them.

put a large sum of troops in a choke point between two of your regions you control. (if you control 2 regions) also, put the same ammount of troops on your border that the other person has