BRG runs a grindy value plan with Lively Dirge recursion and Obsessive Pursuit counters, so Strategic Betrayal is strong here: it exiles their entire graveyard, denying Lively Dirge its targets. They choose which creature to exile, so expect to lose their weakest one rather than a key threat. Duress takes the noncreature spells they rely on, such as Lively Dirge, Obsessive Pursuit, Stir Up Trouble, and Requiting Hex, before they can disrupt your plan. Erode is cut because it hands them a basic land, and their creatures like Greedy Freebooter and Callous Inspector leave value behind when they die. Requiting Hex stays in: most of their creatures, including The Sackville-Bagginses, Biotech Specialist, Gene Pollinator, and Umbral Collar Zealot, are mana value 2 or less, so it is an efficient answer. The two Practiced Offense come out because a sorcery-speed pump is risky against their cheap removal. Keep pressuring with your aggressive curve while disrupting their resources.