Drilla

Drilla Levels are important to determine your drill speed, battery length, mineral-gathering speed, and how many minerals can be stored in your reserve (later used to upgrade Drilla parts or to sell). The motor must be upgraded first to a specific level in order to upgrade the other parts to that level. In other words, motor should be the first upgrade in each level because, without that upgrade, you will not be able to install the other upgrades.

Drilla Images
SOME OF THESE PHOTOS ARE OUTDATED!!!

Levels
We need your help, as this chart is incomplete.