If you just paid some life and named two colors when you played a fetchland, and that land tapped for mana of those two colors for the rest of the game, theyd be better than all the other lands in Modern, but on top of that, they trigger landfall twice, count toward delirium, trigger revolt, allow you to shuffle your deck if you need to, and interact with a variety of other mechanics, as well as marginally thinning your deck. Fetchlands are fantastic, and were allowed to play up to 40 of them, but even though people play twenty to 24 lands, they rarely play more than twelve fetchlands
Instead of traditional land ramp, blue generates tempo through spell velocity and explosive mana turns that enable powerful spellslinger and combo strategies
This makes for deadly assaults and impenetrable defenses
Zevlor, Elturel Exile lets you bounce a targeted effect from once opponent to all of them, which lets you Mindslaver or Worst Fears everyone