Mono-Green Eldrazi floods the board with Eldrazi Spawn tokens and small green creatures en route to Ulamog or Ugin, Eye of the Storms, so High Noon helps restrict their ability to chain spells together. Beza, the Bounding Spring gains meaningful life and can net extra cards or bodies when behind. Avengers Disassembled's 3 damage doesn't reliably clear their bigger threats and is redundant with our other sweepers, so it comes out; the extra Lightning Helix and a land are trimmed to make room. Field of Ruin and Demolition Field stay in to strip Eldrazi Temple and Ugin's Labyrinth before they can cast their expensive top end cheaply.

This Eldrazi ramp-combo deck needs to chain Ancient Stirrings, Malevolent Rumble, and land drops into a big Emrakul or Devourer of Destiny turn, so High Noon slows their assembly significantly while we're comfortable playing one impactful spell per turn ourselves. Beza, the Bounding Spring stabilizes the life total and can generate a Treasure or extra bodies when we're behind on board against their oversized creatures. Avengers Disassembled's 3 damage sweep mode doesn't kill anything relevant here (their creatures are 2/2 or bigger and get bigger fast), so it comes out along with a spare Galvanic Discharge and Lightning Helix, which are too slow against 6/6s and 10/10s. Keep Field of Ruin and Demolition Field in to strip Eldrazi Temple and Urza's Saga, denying their colorless ramp.

Izzet Prowess relies on Mutagenic Growth, payable entirely with life for no mana spent, so Vexing Bauble counters it outright and disrupts their combat math and Dragon's Rage Channeler delirium plans. This is a low-land-count tempo deck, so our land destruction is largely dead and gets trimmed for more impactful sideboard cards. Rest in Peace also strips value from their Lava Dart flashback. Prioritize Wrath of the Skies and Erode to clear Dragon's Rage Channeler and Monastery Swiftspear before they accumulate too much prowess-fueled damage.