Upgrading main Knowledge

Knowledge is laid out in a certain sequence in each category. To unlock Knowledge later in the sequence, you need to learn earlier Knowledge connected with it.

To upgrade main Knowledge, you need to hit its icon and choose how you want to perform the upgrade: instantly for Gold or over time in exchange for resources.

Knowledge that you have already learned has a brightly colored icon, while Knowledge that has not yet been learned is grayed out. Knowledge that is available to be upgraded is marked with a golden frame.

You can only upgrade Knowledge gradually, one level at a time. For example, you cannot upgrade Knowledge from level 1 straight to level 4. Also, to unlock a certain Knowledge, you need to have an Oracle of a certain level.

You can upgrade only one Knowledge at a time, or two at a time with a special Prophet item.

If less than 5 minutes is left until the Knowledge upgrade is completed, the "Boost" button is replaced with the purple "Free" button, which you can hit to complete the upgrade. The free autocomplete time can be increased if you have activated VIP status or have certain bonuses.

You need Manuscripts to upgrade certain Knowledge in the Oracle. You can get them by completing Personal Tasks or by purchasing them in the Clan Store and as part of Bank offers.

Attacks on Uber Invaders also give you a chance to get Manuscripts. The chance of getting them depends on the Skills you have upgraded, Knowledge learned, and the equipment and boosts that increase the Hero's military stats when fighting Invaders. You can see the number of Manuscripts you have in the Resources tab of the My Items window.

You need Totems to learn Knowledge from the Tier VI Troops category, and Obsidian for the Tier VII Troops category. You can get these items as a reward for passing checkpoints in Competitions and for taking top places in the rankings, or you may purchase them as part of Bank offers.