What if the ball had slightly decreased gravity so it floats a little and it started out moving realllly slow - as it travels, it gradually gains weight, speed and damage - at max ramp-up, it causes a small explosion at the point of impact and deals AoE damage, with a direct hit dealing somewhere around maybe 100 damage, and max AoE damage before fall-off is applied dealing maybe 50? It'd be a much harder projectile to land at distance with the slow build-up in both speed and weight making it drop hard, and deal significantly worse damage up close due to its long build-up, but with max build-up it'd be a force of nature crashing straight into the planet!