Apparatus and methods for smoothing and blending drywall mud are provided. The apparatus provides a tool having one or more flexible blades to be applied to unfinished cured drywall mud. The blades may be selectively flexed by driving a displacement member towards or away from the blades. The flexed blades may be used to smooth and feather portions of drywall mud to conceal underlying irregularities and to blend with surrounding drywall. The blades may be biased against the displacement member by biasing mechanisms. The tool may receive multiple blades, including a rough-edged blade for a first pass across the drywall mud and a smooth-edged blade for a subsequent pass across the drywall mud. The blades may be kept in place with connectors which may be flexibly connected to allow for flexion.