Gamma World/YMMV


 * Broken Base: The earlier the edition the more Anyone Can Die. Also, earlier editions had some of the hardest hits of Black Comedy, even compared to the 7th edition (which is more zany than bleak).
 * The middle editions (and especially the D20 edition) gained a more hopeful tone, that something might be done to make the mess less messy, and also that the Player Characters will last for more than a few days. On the other hand, they took away a lot of the elements Played for Laughs, or at least didn't actively try to make them funny.
 * The current edition takes the bizarre comedic aspect of the early editions and cranks it Up to Eleven.