You can go deep on extra combat steps, or you can run a hasty reanimator deck
You can only have one dungeon in your command zone at a time
While the squad ability for it is nice, it has a high cost of needing 4 extra cards to exile for each copy
Its also great tech against Burn, since you can use Petitioners on yourself to guarantee a life-saving burst heal from the card
Since his introduction in the miniatures game, he's been a consistent master of the Psyker magics of Tzeentch, his patron Chaos God known for magic and schemes (and pranks)
Cards like Demonic Tutor and Rhystic Study are certainly way up there but when I draw one of those Im often hoping or planning to turn it into a Dockside and win the game. Matt Sperling, @sickofit Dockside occupies the role of Black Lotus (the most absurdly efficient ritual in the format) on my EDH Power 9 list