Mainboard (60)
Creatures (4)
Instants (16)
Sorceries (13)
Artifacts (7)
Planeswalkers (3)
Dimir Tempo is your most disruptive fair matchup — they combine Thoughtseize and Daze to strip your combo pieces and counter your Doomsday on resolution, while Orcish Bowmasters and Tamiyo pressure your life total and punish Ponder chains. Bring in the additional Veil of Summer to protect your combo turn from Thoughtseize and Force of Will, and Sheoldred to punish their draw-heavy gameplan with Brainstorm and Ponder. Force of Negation provides a free counterspell to contest their interaction on your combo turn. Trim Daze since you're the slower, more reactive combo deck and the symmetrical cost is often a liability, and cut the main-deck Thoughtseize since proactive discard is less valuable when you need to be assembling Doomsday quickly before their disruption accumulates.
Oops! All Spells is a zero-land combo deck that wins by milling itself with Balustrade Spy or Undercity Informer and reanimating Thassa's Oracle or using Dread Return to flashback into a win. This is a pure race — they can goldfish a win on turn one or two, so your goal is to either outrace them or have a piece of disruption backed up by a fast Doomsday kill. Grafdigger's Cage is your most powerful hate piece, shutting off Dread Return, Reanimate, Agadeem's Awakening, and Thassa's Oracle's graveyard-based win condition simultaneously; landing it early can buy enough time to assemble your own combo. Force of Negation supplements Force of Will as free countermagic to stop their key spells like Balustrade Spy or Undercity Informer. Thoughtseize and Daze are trimmed since you want to maximize free interaction and combo speed — the matchup is fast enough that tapping mana for Thoughtseize is often too slow, and Daze is unreliable when you need to go off quickly.
Sneak and Show is a pure combo race — they aim to cheat Emrakul or Atraxa into play via Sneak Attack or Show and Tell before you can assemble Doomsday. Your Force of Will and Daze are the primary interaction, and Teferi, Time Raveler is excellent here since it shuts off their ability to respond at instant speed and prevents them from using Show and Tell on your turn. Grafdigger's Cage doesn't stop Sneak Attack or Show and Tell directly, but it can prevent Atraxa's cascade triggers from finding more threats, making it a useful tax piece. Consign to Memory and Force of Negation come in as additional counterspell coverage for their key spells, particularly Sneak Attack and Show and Tell on the stack. Thoughtseize, Edge of Autumn, and Consider are the lowest-impact cards in this fast matchup where every mana and card needs to be either advancing your combo or stopping theirs.