Spy Missions
The spy missions are one of the more complex parts of Dark Throne, and they sometimes can be confusing if you don't really know the full details behind how they work.

A ”Unknown” spied on you
This is probably the part that gets people most often -- When “unknown” shows up as someone who performed a spy mission against you. Really, this is quite simple. The reason why it shows “unknown”, is because whenever anyone performs a spy mission on your account and they are successful, it shows up as unknown . Of course, if they do a spy mission on you and they lose, it will show their name. If you do a spy mission on them and you win, it shows up as unknown. If you do a spy mission on them and you lose, it will show your name. The logic behind this is: if they successfully did a spy mission against you, that means that they were able to penetrate your sentry defense without being detected, so if you didn't detect them, why should you be able to see who they are???

Spying
You can do a “basic” spy mission to gather information about a player within your attack range. You can get information such as how many miners and troops of a certain type they have, what their fort health is, and their individual statistics. You can send up to 10 spies on a basic spy mission. The more spies you send, the greater the risk of you getting caught by the other player's sentry defense. So, (IMO) it is better to send one spy the first time just to make sure that you can beat them before you risk more spies. Note that the newly added Veteran Spies cannot be sent on spy missions (which also includes assassinations and infiltrations). All this means is that you need to have some extra regular spies (enough to send on spy missions) and the rest can be Vet. Spies, if you want.

Assassinating
Somebody make you mad? Why not assassinate some of his troops? As with spy missions, the more spies you send on an assassination mission, the more likely you are to be caught by the other person's sentries. You can only perform one assassination mission on the same player each day. Each day, you can send only a limited number of spies on assassination missions, given your current spy upgrade. Now you can assassinate a specific group of enemy troops, such as archers, elite archers, or guards, instead of just the defensive group.

Infiltrating
You can infiltrate a player to cause damage to his/her fortification. Again, with infiltrations, the more power you use, the greater your chance of getting caught. As with assassinations, you can only do one infiltration on a player every 24 hours. You can do a total of 5 infiltration missions every 24 hours.

Buying weapons and battle upgrades / Equipping your troops
Another thing that players often don't realize is that when you buy weapons from the armory or battle upgrades, in order for those to have an affect, you must have the appropriate units to support them.

A Battle Upgrades
Note: Before you can purchase battle upgrades, you must have a Citadel or greater fortification. Note: Only the Undead race has berserkers (advanced offensive units) and only the Elves have elite archers (advanced defensive units) Steeds: In order for your steeds to be fully effective, you must have one knight or berserker for each steed that you own. Guard Towers: In order for your guard towers to be fully effective, you must have five archers or elite archers for each guard tower that you own.

Weapons from the Armory
Unlike battle upgrades, any unit of a class can support weapons from the particular class of weapons from the armory. The units are as follows:
For offensive weapons- soldiers, knights, berserkers
For defensive weapons- guards, archers, elite archers
For spy offense weapons- spies, veteran spies
For sentry defense weapons- sentries, sentinels

Each unit of a given class can support one of each type of that class's weapon from the armory, and the elite units can support one of each type of that class's weapon from the armory AND a battle upgrade. Example:
A soldier can support one of each type of offensive weapon, but they cannot support two weapons of the same type. ( a soldier could not support a long sword and a great sword ((both type I offensive weapons)) )
A knight can support one of each type of offensive weapon, plus a steed. (but, like a soldier and any other unit, cannot support two weapons from the armory of the same type)

Attacking
You can only attack a player 5 times in a 24 hour period. The more attack turns you use, the more damage you can inflict, the more experience you can gain, and the more gold you can pillage. Unlike spy missions, when you attack your name will show up in your opponent's logs whether you are successful or not. As with a successful attack, an unsuccessful attack also means more damage--except on your account, not your opponent's. If you lose an attack, you can loose troops, and it is also bad for your account because it lowers your successful attack % on your members page. The more turns you used on the failed mission, the more troops you are liable to lose.

Someone out of your range attacked you
Sometimes it is easy to be under the impression that someone who is not in the 5-level range of your account attacked you. Make sure that you look at the top of the detailed attack log, where it shows what level you both were at the time of the attack.

The Bank
You can deposit your on-hand gold into your bank for safe-keeping or if you want to save it up. You can only deposit 80% increments at a time, and you can only deposit a certain number of times each day, given your current mining upgrade. You can make unlimited withdrawals.

Gold Transfer
You can transfer up to 20,000 gold per player per day. You can only receive a maximum of 100,000 gold in transfers each day. The gold transferred goes directly from your bank account to the other person's bank account, so make sure that you have enough gold in your bank account to cover the transfer.

re-produced with kind permision by Erik