Gruul Ponza attacks our manabase with Mwonvuli Acid-Moss and Thermokarst, and races with Cascade creatures like Annoyed Altisaur and Boarding Party, but our sideboard has little direct interaction with land destruction. Nihil Spellbomb offers modest utility by exiling their graveyard to blunt any recursion and cantrips when it dies, so a small swap is worthwhile. Cut a couple copies of Malevolent Rumble to make room without touching core engine pieces. Since our manabase is resilient via Expedition Map, Crop Rotation, and multiple Tron redundancies, focus on rebuilding lands quickly and racing with our larger threats like Bramble Wurm and Nyxborn Hydra.