Build the Obelisk of Power to begin using Skull Runes to affect different attributes of your Castle and Units.
Skull Runes are powerful emblems that are etched into the Skulls of your fallen enemies. They can be used to cast enchantments over your various Units and Castle, changing their attributes. You will receive Skull Runes every time you Level up in the game. The number of Runes received with each level-up will increase over time:
Levels 2 – 34 will earn you 2 Runes
Levels 35 – 64 will earn you 4 Runes
Levels 65 – 79 will earn you 6 Runes
Levels 80+ will earn you 8 Runes
You may also receive Skull Runes as a reward for performance in a Tournament.
Tap on the Obelisk of Power to access the Rune Tree. On the Tree you will see that all game Units are divided into six Groups. In order to unlock different Unit attributes and branches on the Rune Tree, you must progress through each Group sequentially. You'll notice that applying each Skull Rune takes time – this time will increase with each additional Rune you apply to a Unit.
The minimum amount of Skull Runes required to improve one Unit to its maximum and unlock the next one is 8 (while Occult and Bestiary Units take 10). The maximum amount to be applied to one Unit is 50, and the Food consumption reduction will take 80 Skull Runes if the maximum development level is reached.
IMPORTANT! Once you've applied your Skull Runes, you will only get ONE CHANCE to remove them for free. To remove a Skull Rune, tap on the "Edit" button at the top the Rune Tree and then tap on the "-" symbol next to the Skull Runes you want to recover. When in Editing Mode, you may ONLY remove Skull Runes you have applied and put them back in your Rune Bag. When you have recovered the Skull Runes you want, tap "Apply" to make your changes permanent. You may now redistribute your recovered Skull Rune as you normally would (this includes waiting whilst the Skull Runes are applied).
After your one free edit, you must use Sapphires to make additional changes. The cost of making changes will increase with each additional change, so take your time and plan your strategy carefully!