Spy Combo wants to flood the board with mana dorks and Walls to chain Lead the Stampede and Winding Way into a reanimated threat via Dread Return. Dinrova Horror is the one card worth bringing in: it bounces a key permanent, such as a mana source or a Wall, while forcing a discard, which disrupts their assembly. Ancient Grudge is not worth a slot. It only destroys artifacts, and their Overgrown Battlement and other Walls are creatures, so the only real targets are a couple of Lotus Petals. Bedeck gives a creature +3/-3 until end of turn, which kills their many 0/3 Walls and mana dorks as well as Balustrade Spy, so it stays in. Breath Weapon's 2 damage mostly whiffs on their 0/3 to 0/5 Walls, so it comes out. Keep Moment's Peace and Stonehorn Dignitary to blunt their eventual big attackers like Troll of Khazad-dum.