'''{{Anchor|Learn through Imitation}} {{Ex}}:''' A humandrill's most impressive ability is its nearly peerless potential. Humandrills learn fast, and their sophisticated and adaptive mindsets allows them to learn and develop with nearly no limit. When surrounded by sentient creatures, a humandrill advances with class levels instead of [[SRD:Hit Dice|Hit Dice]], though the class it gains depends on the humandrill's exposure. When living in or near a settlement of sentient creatures, humandrills most often gain levels in the favoured class of the most numerous (or most visible) species. Observing conclaves or societies that focus heavily on specific trades or classes generally make the humandrill develop and gain ranks and levels in the appropriate skills and classes. Humandrills of sufficient intelligence and immersion in sentient culture can even pick and choose what skills they learn. Regardless of their chosen class or profession however, the maximum class level a humandrill is capable of reaching is equal the level of the observed creature with the highest level in that class -3. A humandrill receives all benefits from any level it gains, including an ability score increase every 4 levels.

Humandrills cannot multiclass. They pick one class path depending on what options are available to them, and stick with it. However, if sufficiently many creatures focus on one specific prestige class, the humandrill may take said prestige class if it meet all prerequisites. A humandrill may only pick class options that are represented within the group of people it imitates. As such, if a humandrill would gain its abilities by observing a conclave of wizards that specialize in [[SRD:Transmutation School|transmutation]], the humandrill will also have a specialization in transmutation.