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A hero at level 20 has almost 82,000 experience points.
A hero at level 21 has almost 98,000 experience points.
If a hero has the "Learning" skill at the expert level, even from level 1,
then their experience points at level 20, compared to a hero who does not have
this skill, will increase by 15%, i.e., it will be about 94,300.
Therefore, the "Learning" skill does not increase the hero's level by even 1 by level 20.
