Aside from hidden subclasses, I would like there to be gameplay features (not necessarily subclasses) that require specific actions, decisions, characters, or roleplaying to obtain. In the realm of subclasses, I am reminded of becoming a Blood Mage in Dragon Age: Origins requires making a deal with a demon (which I've usually done as a mage... I just can't help myself). I know that spells, weapons, armor, and the like can be hidden throughout the world, but it would be cool if other abilities and gameplay features were strewn about as well, beyond just the character creator. Maybe a hidden deity or patron you can switch to as a cleric or warlock is hidden somewhere? Maybe you can become a cleric of the Absolute? Or cut a bigger deal with Raphael? Or maybe find a way to turn as a mindflayer while somehow retaining your mind/soul (maybe through a necromantic art?)? Then unlock worship of Ilsensine? Just having hidden build features throughout the story and world would be cool.
