Do I need to buy Hero, Champion, and Royal together? Or is one them a version that includes the others?

I see the White March expansion pass actually explains that it includes both The White March: Part I and Part II. For the base game, however, it's not that clear. It looks like there are more items than there really are and leaving them checked would result in buying the same content twice.

Further the White March items have the strike through on the amount and the same amount next to it. Was there an error or are they not 50% off as was implied?

Its just editions with bonus content... the hero edition has everything essential to the game, the more expensive ones include the soundtrack, making of videos (i think) and stuff like that. You only need one of them.

That's what's bugging me too, and the reason I'm holding off, is someone contacting support on this?

It's not an error. The expansions are part of the same franchise so why wouldn't they be displayed?

The price doesn't show them as being 50% off. So why would they be displayed as if they're on sale?

i think its just a tease. Wouldnt expect the addons to be reduced so early after release...

got a reply from support:

as you can read in the news post regarding the release of The White March Part 2, the DLC and the Expansion Pass for Pillars of Eternity aren't actually discounted; the discount only applies to the base game versions:
https://www.gog.com/news/release_pillars_of_eternity_the_white_march_part_ii
However, with the way our promo page for this sale was set up, it was confusing as the DLCs were listed with the reduced versions of the base game. We have changed this now to accurately reflect the 50% discount on the base game versions and the fact that the DLCs are not discounted at the moment. I apologize for the confusion.
Regards,

Lisa
Customer Support Representative
GOG.com