He is encountered by Batman in the sewers beneath Blackgate Penitentiary; Batman seemed to have met Grundy at some point before, since he knew his name. Batman defeats Solomon Grundy by tricking him into the electrical wires and then beating him up; after traversing the nearby area for a while, the unconscious Grundy will vanish, implying he retreated back to where he came from. Although he does not appear in Batman: Arkham Knight, one of the alleys has a room with Solomon Grundy's wanted poster as well as a gold gramophone reproducing the "Solomon Grundy, Born on a Monday" nursery rhyme, which is performed by a childish voice.