High Ground

 is a game mechanic that first debuted in BTD6. Towers with High Ground will negate Line of Sight, a mechanic also introduced in BTD6.

High Ground has no effect on tower range, and is mostly in maps by themselves, but there are ways to make High Ground, like the Carrier Flagship's higher decks, which is the most notable use of High Ground. However, Etienne and his abilities, Monkey Aces and all upgrades, and Heli Pilots and all upgrades have High Ground by default. The Buccaneer's Aircraft Carrier upgrade's planes also have High Ground, despite the Buccaneer being a water tower. The Bloon Exclusion Zone's two top barrels also have this mechanic. Towers influenced by Door Gunner also have High Ground.