In a footnote in a two-page order issued in 2018, the Delaware Supreme Court quietly reminded corporate law practitioners that, per the 1989 case of Mills Acquisition v. Macmillan, a complaint seeking post-closing Revlon damages can survive a motion to dismiss without pleading nonexculpated breaches of fiduciary duty by a majority of directors so long as a single conflicted fiduciary deceived the entire board. See Kahn v. Stern, 183 A.3d 715 (Del. 2018) (TABLE). In the three years that followed, this "fraud-on-the-board" theory of liability has received long-form discussion in at least eight published Delaware opinions and evolved into a Swiss Army knife for stockholder-plaintiffs—indeed, Delaware courts have recently applied the once-obscure theory to serve at least three distinct doctrinal ends. This article describes, at a high level, what fraud on the board is by pinpointing the various doctrinal roles it has played in three recent opinions issued by the Delaware Court of Chancery.