Blue Diamond

Blue Diamonds are the free currency in game, with blue diamonds you can rush researches,

constructions and training as well as buy advanced items to construct end tier buildings.

Sources

1. When clicking on your power number in the top left, you get to the 'Combat Ability Assesment' page, every day you can claim gifts based on your combat ability, including blue diamonds.
2. Iron Bank Once your castle becomes level 17 you can construct the Iron Bank, early on the best level for your bank will be level 3. Make sure you save up and invest 10,000 Blue Diamonds every month, this will almost double them over this time.
3. Training Grounds Another great source of daily diamond income is the Training Grounds. Especially once you reach the top 100, but also ranging from 100-500 you will get a steady diamond income every day.
4. Rebel Leaders Every day you can spend Motivation to hit Rebel Leaders, you can boost this significantly by research in the Exploration and Pacification tree in your Maester's Tower. They have a good chance to drop diamonds.
5. Rebel Groups Rebel groups can also boost your diamond income, by using Endurance you can at least hit 5 Rebel Groups a day. Elite Groups will be harder to kill, but yield greater rewards.
6. Rebel Camps Once you are in an alliance, strong players can initiate rallies on camps. Make sure you join enough to have all your slots filled all the time in the Merchant Guild.
7. Alliance Gift Every alliance member that kills a Rebel Leader will generate a chest in the Alliance gift section of your alliance screen. Those rarely contain blue diamonds, but a lot more chance of diamonds in the Alliance gift will be when you alliance members buy packs from the Great Discount store.
8. Recurring Events A recurring event is an event that refreshing and keeps coming back, like the events in the Great Discount store, but also the Elite, Daily and Normal event. Saving up speed up items is the best way to go! Finish a big research when Elite, Normal and Daily all improve by Research Points or train a lot of soldiers when they all give points for training troops. They often come with decent diamond rewards.
9. Events There are a multitude of events, sometimes 5 or 10 at the same time. Participate in all of them as much as you can, there are many diamond rewards in those events.
10. Active Reward Active reward is your checklist of your daily chores. It is not hard to complete sufficient quests to get both wheels of fortune spinning, often with up to 3,000 diamond rewards! Also when reaching 1,000 points in a week you get an additional 200 blue diamonds.
11. Nobility You get a small diamond payment based on your nobility every day.
12. Monthly Card If you can spare the money for the monthly card, which is 10$ per month, do it. You will recieve 400 blue diamonds every day as well as an initial bonus when refreshing the card.
13. Alliance Get yourself in a decent or high alliance, with some money spenders, you alliance gifts will increase significantly!

Spending Diamonds

Early in the game, save up your diamonds for the following items:

• Battle Codex
• Book of Confession
• Mask of the Faceless Men
• Moneylender's Contract

These will help you construct the buildings you need to progress both your power and your research. Still, it is usually a good idea to spend 500+ diamonds every day for the Active Reward.

The VIP Shop can save you a lot of blue diamonds, when you do not have to save for a building, make sure you buy from there all you can.

Later on, you want to focus on spending the diamonds in events like the Westerosi Navigator (which is a bit of a gamble) and spend them on buying event items in bigger events like King's Festival. But your number one priority is finishing your Bannerman Hall and other buildings.

Unless you really have an abundance of blue diamonds, don't waste diamonds on speedups, you will seriously hurt your progression if you don't save all for buildings. You will need several hundred thousand.

See also:

• How to spend them (after your buildings are complete)

Other

Diamonds can be received as direct currency but also as the following cards: TBD