Mainboard (60)
Creatures (34)
Instants (6)
Sorceries (3)
Boros Energy is an aggressive deck that pressures you with efficiently-statted creatures like Ragavan and Guide of Souls before you can assemble a Living End. Dismember answers early threats like Ragavan and Ocelot Pride at instant speed without disrupting your cascade plan, which is critical since you cannot afford to tap mana for interaction on your cascade turn. Force of Vigor comes in to destroy Goblin Bombardment, which can sacrifice their entire board in response to Living End and negate your graveyard reset. Sink into Stupor and Deceit are the weakest cards against a fast creature deck with no counterspells mainboard, as their discard/bounce effects are too slow. Post-board they bring in Blood Moon and Deafening Silence, so keep Boseiju and Otawara active as answers, and try to resolve Living End before they can stick a hate piece.
Jeskai Blink is a fair tempo deck that disrupts your combo primarily through Consign to Memory on the cascade trigger, backed by pressure from Ragavan, Phelia, and Quantum Riddler. Mystical Dispute comes in as efficient interaction to win counter battles over Living End, and becomes even more important post-board when they add Mystical Dispute and Strix Serenade of their own. Dismember efficiently answers their key creatures—Ragavan stealing cascade spells off Shardless Agent is a backbreaking line, and Phelia generates compounding blink value if left unanswered. Colossal Skyturtle is trimmed because its slow cycling and channel mode are too low-impact against a deck that can blink it away or simply race you, and Sink into Stupor and Deceit are cut as the dedicated counterspell and removal slots serve you better than situational bounce or soft counters here.
Affinity is a fast artifact-based deck that wins through Kappa Cannoneer growing out of control, Urza's Saga tokens, and Weapons Manufacturing generating artifact fodder. Force of Vigor answers Urza's Saga or key permanents like Pithing Needle and Engineered Explosives for free, which is critical since Affinity can present a lethal board before you stabilize. Dismember handles Kappa Cannoneer efficiently without needing to interact through countermagic. The Living End cascade plan is excellent here since your cyclers trade favorably against their artifact creatures in mass reanimation, so you want to protect it with your Force of Negation suite — be wary of their Tormod's Crypt, Grafdigger's Cage, and post-board Damping Sphere. Sink into Stupor and Deceit are trimmed as the slower interaction pieces are less impactful against their aggressive, low-to-the-ground gameplan.