Olgar Shiverstone
Legend
How about 1E's approach: psionics rules everything else and breaks the game?
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Mechanically, I agree with this approach.
For presentation, I hope 5E psionics are in a separate module in a separate book so I can safely continue to ignore them.
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I liked the direction 4E moved in - Psionics was effectively another style of magic, and shared a lot of the basic rules. It was just different enough to feel different, but there was only a little additional mechanics required.
I also prefer, fluff-wise, the psionics-as-willpower-magic as opposed to the psionics-as-talents/disciplines (which, due to my age, puts me in mind of 70's sci-fi and not fantasy). I quite liked Rolemaster's take on that, and 4E's power sources with psionics being one of a set, sat well with me for the same reason.
Mechanically, I agree with this approach.
For presentation, I hope 5E psionics are in a separate module in a separate book so I can safely continue to ignore them.