They go for fifty bucks retail, and for hundreds of dollars on the secondary market, and can yield some seriously valuable cards
Eldrazi players have to either upgrade their Zhulodok decks, change it to Ulalek, or build a whole new deck
There are also iconic red combos like Splinter Twin/Kiki-Jiki, Mirror Breaker + Zealous Conscripts, Godo, Bandit Warlord + Helm of the Host, or Bonus Round + Storm spells
Adarkar Valkyrie always makes me chuckle whenever I run across it while deckbuilding
The deck revolves around casting an army of spider creatures and then using Shelob's ability to give your entire army deathtouch, ward 2 and most importantly effectively resuscitate your opponents' creatures as tokens
Kotis, the Fangkeeper says that you exile X cards from the top of your opponent's library and you may cast only the spells exiled