Adept Watershaper Adrix and Nev, Twincasters Alandra, Sky Dreamer Ambassador Laquatus Aquitect's Will Araumi of the Dead Tide Arctic Merfolk Atlantean Cavalry Atlantean Skirmisher Attuma, Atlantean Warlord Augur of Bolas Benthic Biomancer Benthic Criminologists Benthic Explorers Bioluminary Blockade Runner Brineborn Cutthroat Cache Raiders Caller of Gales Campus Composer Cascade Seer Cenote Scout Ceta Disciple Champions of the Shoal Cleric of Chill Depths Cold-Eyed Selkie Combine Guildmage Coral Commando Coral Fighters Coral Merfolk Coral Trickster Coralhelm Chronicler Coralhelm Commander Coralhelm Guide Cosi's Trickster Crackling Triton Cursecatcher Dakra Mystic Dalakos, Crafter of Wonders Darting Merfolk Daughter of the Deep Deepchannel Duelist Deepchannel Mentor Deepfathom Echo Deeproot Champion Deeproot Elite Deeproot Historian Deeproot Warrior Deeproot Wayfinder Deeptread Merrow Deepwater Hypnotist Deepway Navigator Disruptor of Currents Drowner Initiate Drowner of Secrets Eclipsed Merrow Emperor Mihail II Empress Galina Emry, Lurker of the Loch Enclave Cryptologist Enclave Elite Encumbered Reejerey Evidence Examiner Expedition Diviner Expedition Lookout Fallowsage Floodpits Drowner Forensic Researcher Forerunner of the Heralds Frostwind Invoker Furtive Courier Gaea's Skyfolk

All cards printed with the changeling ability are shapeshifters but there are lots of shapeshifters that arent changelings, like Aetherling and Altered Ego
This deck plays like a chaotic balletcreatures bouncing between your hand, graveyard, exile, and the battlefieldtriggering effects all along the way
Steelclad Serpent Getting better, but Steelclad Serpent is still unplayable
But I can see this as a good part of a vigilance-themed deck built around something like Roon of the Hidden Realm
This works well in tons of shells