Not So Different/Tabletop Games

Examples of in  include:

Card Games

 * In Magic: The Gathering, colors across from each other on the color wheel are philosophically opposed, but there are often surprising similarities. A card which made all creatures unblockable would be blue while a card that made all creatures unable to block would be red, despite those two having the same mechanical effect.
 * White and Black tend to be the most egregious examples. Both handle lifelink, both have a similar keyword pool, both deal in religion, albeit through different lenses. Needless to say, the most blatant mirror cards (White and Black Knight anyone?) tend to cross this pairing.
 * Black also has some interesting things in common with its other rival, Green. They're the most common places to find the abilities of Regeneration (recovering from lethal wounds) and Deathtouch (venom that can prove lethal even with a scratch).
 * Just so the other three enemy color pairs don't feel left out: Both blue and red mess around a lot with instants and sorceries, redirecting them, copying them, you name it. Both red and white work on the premise that the ideal tactic is to take a large army and give them a common goal, and tend to be aggressive. Blue and green are probably the least alike, but both like to take creatures and make them better - although blue changes them For Science! and green changes them as a form of natural evolution.

Tabletop RPGs

 * In Hunter: The Vigil, the Loyalists of Thule are a group of monster hunters who strive to atone for the fact that some of their old ideals influenced the Third Reich, and that some of their people even participated in the Holocaust. They've maintained this as their sole and driving purpose for sixty years, and completely avoided any rise of Neo-Nazi sympathies within their ranks. How? By brutally murdering any member who so much as suggests that the group might not need to obsess over the whole Nazi thing quite so much.