Mono-Green Eldrazi wants to grind with Emrakul, the Promised End and Devourer of Destiny while using Urza's Saga and Springleaf Drum for ramp. Collector Ouphe shuts off the activated abilities of their artifacts, including Springleaf Drum, Talisman of Resilience, Blade of the Bloodchief's equip, Haywire Mite, and Soul-Guide Lantern. It does not stop Urza's Saga, which is an Enchantment Land, and it doesn't hurt us: Amulet of Vigor is a triggered ability, so it keeps working. Dismember (-5/-5) cheaply answers Basking Broodscale, Sowing Mycospawn, or a small blocker, but it will not kill Devourer of Destiny, which is a 6/6 and survives as a 1/1. That matters since this matchup is often a race to resolve Primeval Titan or Scapeshift. Trim Malevolent Rumble since Boseiju, Who Endures and raw land drops matter more than digging when the opponent isn't combo-focused here, and cut the extra mill from Aftermath Analyst since self-mill is low-upside when Soul-Guide Lantern and Kozilek's Command can exile our graveyard. Keep Boseiju in to fight Urza's Saga and Ugin's Labyrinth.

This matchup is a race to assemble a combo: Force of Vigor can destroy both Blade of the Bloodchief and a Vexing Bauble (or other one-mana artifact) in one card, which directly disrupts the Basking Broodscale loop, and it can even be cast for free by exiling a green card if it's not your turn. Dismember kills Basking Broodscale (toughness 2, or 3 with one Adapt counter, well within -5/-5) before they can equip Blade and go off, and can also answer Glaring Fleshraker. Note that it does not kill Devourer of Destiny, which is a 6/6. Cut Malevolent Rumble since it's a slow dig spell compared to cheap removal in a race, and trim Aftermath Analyst's self-mill since you want cards in hand to interact rather than cards in the yard. Prioritize holding up Dismember on their turn once they have Blade and Broodscale both in play.

Izzet Prowess is a fast aggressive deck with no removal-proof blockers, so a 2/4 Reach body like Six helps stabilize the ground and blocks Monastery Swiftspear or Slickshot Show-Off profitably while milling for extra land drops. Collector Ouphe is mostly a sideboard trim here since the opponent has few activated abilities to shut off (Cori-Steel Cutter's equip is activated, but this is a minor upside), so only bring it if you need more bodies. Cutting Hanweir Battlements removes a slow colorless land that doesn't help you stabilize against burn, swapping it for a land-adjacent creature; keep in mind Six still counts as a creature land replacement rather than a land itself, so only make this swap if you have another blocker plan. This matchup is still primarily about resolving a Titan or Scapeshift before dying, so don't over-board for defense at the cost of mana consistency.