In most everything related to her, the Raven Queen from Dungeons & Dragons Fourth Edition is portrayed as a Kelemvor Expy who's True Neutral and represents death as a natural part of life and its inevitable end. Except for one sidebar in Divine Power, where she's suddenly a cacklingly evil madwoman who killed Nerull to take his place and was only forced into her current role by the other gods... who she wishes to overthrow so she can become a true Nerull Expy, seemingly for absolutely no other reason except that a goddess of deathmustbe evil.
Warhammer 40,000 codex fluff has somewhat turned to this, YMMV of course. The most recent is the Grey Knights killing a coven of Sisters of Battle, then coating their armor in the latter's blood (something usually reserved for Khornate worshippers). This is in large part due to GW's new trend of Ret Conning old fluff rather than moving the plot forward. However, plotwise the fluff has already reached the literal last few minutes of the 41st millenium (the Medusa Campaign, taking place almost 5 real-life years ago, was said to have ended on the last year of the 41st millenium) and it would be hard to keep calling it "in the 41st millenium" when it's already 41,001, so it might be justified.
Technically not an example of the trope since the official policy makes them Retcons. This policy has been in effect since 2nd edition.
The two examples cited are examples because they do contradict characterizations that are still considered canon.
This occurs sometimes in the shadowtalk sections of Shadowrun sourcebooks. It's somewhat inevitable, given the Loads and Loads of Characters featured in those sections (though the number of different characters has gone down in 4th Edition). The sourcebook Cyberpirates was especially bad for this, turning the poster Dr. Bones from a dwarf computer company CEO with a Star Trek themed handle to an actual medical doctor who made excuses and defended the racist, experimenting-on-metahumans corporation that trained him. The poster Truthseeker was also altered from an anti-meta racist who thought there was a grand metahuman conspiracy to a pro-meta conspiracy theorist. Fortunately, the derailment of those two characters seemed to begin and end with that book.
