Shadowspear helps ensure you have consistent access to lifegain and trample for your ring bearer, with the side benefit of letting you remove hexproof and indestructible from opposing threats, and can be searched up with Urzas Saga
"Geistflame Reservoir" gains charge every time an instant or sorcery is cast, and can deal damage based on how much charge it gains
Blake Rasmussen (September 6, 2016)
Karakas, along with the next card on this list (which is on it for another reason), were casualties of the formats growth
Not all rats lean into this strategy, however
Madison Li Elder Owyn Lyons James, Wandering Dad Jason Bright, Glowing Prophet Liberty Prime, Recharged Marcus, Mutant Mayor Nick Valentine, Private Eye Piper Wright, Publick Reporter Raul, Trouble Shooter Red Death, Shipwrecker Rex, Cyber-Hound Shaun, Father of Synths The Master, Transcendent The Wise Mothman