Leyline of the Void is the main plan here. It exiles every card that would go to their graveyard, which blanks the graveyard half of Malevolent Rumble, Aftermath Analyst's mill and land-return, Echoing Deeps copying a land from a graveyard, and Shifting Woodland's delirium. Lands they sacrifice to Scapeshift are exiled too. Green Sun's Zenith shuffles itself back into the library rather than the graveyard, so Leyline does nothing against it. Consign to Memory replaces Harbinger of the Seas. Harbinger only makes their nonbasic lands Islands, and those lands keep their printed abilities, so it does not slow the bounceland or Saga engine, and Primeval Titan still searches for land cards as normal. Consign counters colorless spells like Amulet of Vigor, and it counters triggered abilities such as Primeval Titan's enter and attack triggers, Spelunking's enter trigger, bounceland enter triggers and Urza's Saga's chapter III. Keep Force of Negation and Spell Pierce in. Amulet of Vigor, Spelunking, Scapeshift, Malevolent Rumble, Green Sun's Zenith and Summoner's Pact are all noncreature spells and legal targets. Force of Negation can be cast for free on their turn. Keep Counterspell for Primeval Titan and Cultivator Colossus. Fatal Push is the card to trim. It can never kill Primeval Titan (mana value 6) or Cultivator Colossus (mana value 7), and it only hits small creatures like Arboreal Grazer and Aftermath Analyst, so one copy stays and the rest come out.