Hi all, guys.

Well, at last, I have some will to translate my own sketches guide from rus. Hope, it will be helpfull.

Here are some abbreviations I will be using:

1. Rss – resources. 
   
2. 10k = 10 000. 10kk = 10 000 000. 
   
3. Sapph – sapphires.  
   
4. Skt – sketches. 
   
5. Off – offence, def – defense. 
   

So, sketches are special resources. They are needed for buildings upgrade above standard levels.

They can be bought by sapphires, bigger package – lower price (1 skt = 25 sapph, 1000 skt = 10r sapph (10sapph/1skt).  Sometimes we have discounts 30% in our game. Sketches also can be found in some tournaments rewards.

So, what can be upgraded and worth it or not:

• Infantry. The infantry mechanic stay the same. Upgrading will only increase percentage of offence troops, that accidental died in castle defense, available for free revive. The amount of defense troops free revive will stay the same – 30%. 
  

• Warehouses and Barns +1 will give +20k of each rss in storages, +2/+3/+4 will give +10k, +5 will give much-much more. In my opinion only +1 worth taking. FYI standard storage limit is 211k of each rss, max with +5 upgrades – 1.5kk rss.
  

• Training buildings have only +2 upgrades. +1 will increase training time to 4 days and will auto hide new trained troops. +2 will increase training time to 5 days and will give +10% def and off bonuses for trained unit type.
  

• Catacombs upgrade increase amount of saved rss. +1 = +7k saved rss, +2/+3/+4 - +5k rss. So 24lvl catacombs will save 40k of each rss.
  

• Production building upgrades - +1 will give +120 rss/hour, further upgrade will give +100 rss/hour. 39 and 40 lvl of Mine and Townhouses will give also off and def bonuses, Farms – food consumption reduction.
  

• Forge and Dungeons have only +2 upgrades. Each upgrade will give +5% production boost, +20% in total. 
  

• House of Scrolls have only +2 upgrades. Each upgrade will give +5% discovery speed, +50% in total.
  

So, “edible” and “inedible” in my opinion:

• Infirmary. I’ve been raided rarely in my 2 years game existence. Ofc, I’m in peaceful alliance and destination. So it’s now critical for me. Hope I have an opportunity to revive free 50% of deff troops, but increasing free revive off troops in castle defense with boosts and auto hide items and features seems useless for me.
  

• Storages – you will need more than 211k rss only for heavy units upgrades above standard 20 lvl. For others – it’s not need. Almost all rss will be needed to maintain full training queue.
  

• Increase training time and auto hide – nice features. In my situation it’s useful for units that are always in training – infantry and cavalry. I’ll take it after production upgrades. Not critical but nice. 22 lvl with +10% off and def will be much better but more expensive.
  

• Catacombs – hide more, save more. It’s better than Infirmary, but worst than rest.
  

• Forge and Dungeons upgrades will be the best for me after production upgrades. Use calculators to find out what will be better - +100 rss/hour (and price in skt) or +5% production boost (and skt price).  
  

• Production upgrades are on the first place for me. +1 should be taken 100%, further upgrades as necessary.
  

• House of Scrolls – as necessary.
  

Upgrades cost in sketches:

• Barns +1 - 75; +2 - 165; +3 - 220; +4 - 365; 25 lvl - 465. 
  
• Warehouse +1 - 60; +2 - 150; +3 - 200; +4 - 350; 25 lvl - 450. 
  
• Infirmary +1 - 800; +2 - 1550; 16 lvl - 2500. 
  
• Forge +1 - 550; +2 - 1800. 
  
• Dungeons +1 - 550; +2 - 1800. 
  
• Catacombs +1 - 150; +2 - 350; +3 - 600; 24 lvl - 1200. 
  
• Townhouse +1 - 120; +2 - 200; +3 - 300; +4 - 450; 40 lvl - 620. 
  
• Mine +1 - 120; +2 - 200; +3 - 300; +4 - 450; 40 lvl - 620. 
  
• Farm +1 - 180; +2 - 260; +3 - 420 ; +4 - 620; 40 lvl - 800. 
  
• Sentry House +1 - 600; +2 - 1920. 
  
• Order of Knights +1 - 800; +2 - 2560. 
  
• Council of Mages +1 - 800; +2 - 2560. 
  
• House of Shadows +1 - 1000; +2 - 3200. 
  
• House of Scrolls +1 - 600; +2 - 1500. 
  
• Eagles Nest +1 - 800; +2 - 2000. 
  

And summary:

Sketches won’t be needed for most of players in game system free to play with no donations. You can get some sketches free in some tournament rewards and standard building levels are rather comfortable to play.

For the rest – hope my info will be useful.

PS Lost arts upgrade cost above 30 lvl will be sometime.