Scrap Trawler does wild recursion stuff when all artifacts can be self-sacrificing Clues
Last but not least, rotation is right around the corner
One of my early favorites, and seeing the rest of the set hasnt dampened my enthusiasm for Heliod
You can also sacrifice Knights of San d'Oria/Ranger-Captain of Eos to prevent your opponents from casting noncreature spells on this turn
It's far too one-dimensional to play, and even when it's in full flow, each sacrifice or life gain just sets off a sequence of events that you need to resolve over and over again, but many aren't all that interesting to deal with
Mike Lim aka Daarken is another prominent exponent of these darker themes, with lovely cards like Shipwreck Singer and Bloodhusk Ritualist: Looking at these images, it might not be entirely unfair to guess that he's a bit of a Luis Royo fan