http://www.gamesas.com/topic/1452467-game-sales-and-deals-steam-gog-gamersgate-impulse-desura-gmg-etc/
This thread is for the discussion of gaming deals found on http://store.steampowered.com/, http://www.gog.com/, http://impulsedriven.com/, http://www.desura.com/, http://www.greenmangaming.com/and other sites or stores.
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The Legacy of Kain series is one of the most underrated games ever, storywise. I have seen other sites have the same deals, and one thing they have in common is that they don't include Blood Omen. Which is the beginning of the series and explains Kain's story.
The series is split between two sets of games. The Blood Omen series: Deals with you as Kain and his dark rise and ascension to godhood.
The Soul Reaver series: Deals with you Raziel, Kain's eldest child and lieutinent.
The one titled defiance was the last in the series and brings both Kain and Raziels stories to a close.
Ok, from what I seen this bundle deals primarily with Raziel's portion of the story. Imo, that forces you to side with Raziel since Kain's story is never fully explained.
For the record I started the series back in '96 with Blood Omen. So I always liked Kain more than Raziel.
I suggest you hunt the two Blood Omen games, to better understand the story. Also here's my suggested play order: Blood Omen 1, Soul Reaver 1, Soul Reaver 2, Defiance and Blood Omen 2.