Skull Tweak in Bloons TD 6 becomes extremely demanding beyond Round 100 on Hard difficulty, as powerful BADs, fortified MOAB-class bloons, and increasingly intense late-game waves put your defense under constant pressure. The map’s skull-shaped layout, water areas, bridges, and line-of-sight blockers make efficient use of every available placement spot crucial for maximizing damage and coverage. To survive the highest rounds, you need a carefully optimized defense with powerful DPS, strong MOAB control, and reliable support to handle the escalating late-game pressure.