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In fact, most decks built around ex cards are pretty damn powerful
Its an Always Watching on a body, and its almost always available as a lower-power creature to trigger coven
(For a deeper look at some of the best decks of that time period, Randy Buehler took a look with his article "Throwback Standard Gauntlet 7: Worldwake ".) While we didn't end up hitting the card where Standard would have wanted it to be for the best Standard environment long term, Jace certainly became even more iconic after Jace, the Mind Sculptor was introduced and has proven to be a format staple for many of our older formats

Advanced Search Sets Random Syntax Anurid Scavenger Arms Scavenger Atzal, Cave of Eternity Battlefield Scavenger Bloodfell Caves Calamitous Cave-In Captivating Cave Cave People Cave Sense Cave Tiger Cave of Temptation Cave of the Frost Dragon Cave-In Cavern Crawler Cavern Harpy Cavern Lampad Cavern Stomper Cavern Thoctar Cavern Whisperer Cavern of Souls Cavern-Hoard Dragon Cavernous Maw Caverns of Despair Caves of Chaos Adventurer Caves of Koilos Celestine Cave Witch (playtest) Chromatic Lantern Coati Scavenger Cryptic Caves Deathgorge Scavenger Deep-Cavern Bat Deepcavern Imp Diregraf Scavenger Dreadwing Scavenger Dromar's Cavern Duergar Cave-Guard Dukhara Scavenger Forgotten Cave Frilled Cave-Wurm Gemstone Caverns Gimli of the Glittering Caves Goblin Caves Hollow Scavenger Hollow Scavenger Hollowhenge Scavenger Ice Cave Icecave Crasher Merfolk Cave-Diver Midnight Scavengers Moldgraf Scavenger Moonlit Scavengers Moria Scavenger Moriok Scavenger Nighthawk Scavenger Nikara, Lair Scavenger Optimistic Scavenger Pelakka Caverns Rhystic Cave Ronin Cavekeeper Sandbender Scavengers Sandsteppe Scavenger Scavenged Blade Scavenged Brawler Scavenged Weaponry Scavenger Drake Scavenger Folk Scavenger Grounds Scavenger Hunt Scavenger Hunt Scavenger Hunt Scavenger Hunt Scavenger Hunt

They also all have an activated ability, which works with four of Bloomburrows creature types