This doesnt change when the card can be cast
The majority of Sen Triplet wins I eventually find are cobbled together through an absurd collection of cards from multiple opponents and held together by Scotch Tape
Its drawback may look like its very punishing and can allow the opponent to surprise you via a mid-combat spell, but I never really saw that scenario play out since its damage prevention ability is a a conditional static ability so as long as its on when damage is dealt, it wont be prevented. (Thank you, @fenaris!) It usually plays out somewhat like a colorless Ashenmoor Gouger / Chimeric Idol where you typically dont bother trying to block with it (why am I blocking with my aggro guys anyway?) and, if need be, you cast a spell pre-combat to activate it (typically I used a large coin, like a quarter, to denote whether it was on or off)

Amber Gristle O'Maul Balthor the Defiled Balthor the Stout Barrowin of Clan Undurr Bruenor Battlehammer Cadric, Soul Kindler Cayth, Famed Mechanist Depala, Pilot Exemplar Gimli of the Glittering Caves Gimli, Counter of Kills Gimli, Mournful Avenger Giott, King of the Dwarves Glin, Dwarf Emissary Hofri Ghostforge Irini Sengir Koll, the Forgemaster Krile Baldesion Magda, Brazen Outlaw Magda, the Hoardmaster Papalymo Totolymo Rankle and Torbran Reveka, Wizard Savant Reyav, Master Smith Shantotto, Tactician Magician Sram, Senior Edificer Sram, Senior Edificer Tataru Taru Torbran, Thane of Red Fell Vihaan, Goldwaker