Vakama is trying to master his new powers while he waits for the inevitable arrival of the other Hordika.
Mother Nature speaks to the Dwarfelles and holds Thunderella accountable for not mastering her powers.
In Operation Chaos, a werewolf depends only on a light trigger to master his powers, but his wife, a witch, must study to acquire hers.
Rambeau sought out the Avengers for help in mastering her new powers and became a member-in-training of their group.
Carter also witnesses him ordering the "longnecks" sent to get the "younglings" before they master their powers.
Even if this creature which has stolen my skin hasn't mastered my mental powers, Baby won't question him.
These young mages had mastered their powers when they were 13.
And if he could master his powers, why then he might be able to do anything.
Master your fears and you will master your powers.
It takes decades for them to learn how to master their powers.